DEPARTMENT OF CHEMISTRY

UNIVERSITY OF SWAZILAND

MAY 2015 FINAL EXAMINATION

TITLE OF PAPER

COURSE NUMBER

TIME

Important Information

INTRODUCTION TO ANALVTICAL CHEMISTRY

C204

3 HOURS

1 Each question is worth 25 marks

2 Answer any four (4) questions in-this paper

3 Marks for ALL procedural calculations will be awarded

4 Start each question on a fresh page of the answer sheet

5 Diagrams must be large and clearly labelled accordingly

6 This paper contains an appendix ofchemical constants

7 Additional material graph paper

You are not supposed to open this paper until permission has been granted by the chief invigilator

QUESTION 1

a) Define or explain the following

i) Accuracy

ii) Determinate error

iii) Precision

iv) Indeterminate error (4)

b) i) List the four main types ofdeterminate error (2)

ii) Give a brief explanationdescription of each of the types of determinate error you listed in

(i) (4)

iii) Explain two ways which can be used to detect determinate errors (A-)

c) The following data were obtained for the analysis of a standard soil sample containing

the analyte acenaphthene a known carcinogen The concentration ofacenaphthene

in the sample is given as 32 ppb

Determination Acenaphthene (Ppb)

1 30

2 29

3 31

i) Calculate the mean of the data set

ii) Calculate the relative error of the mean of the data set

iii) Calculate the standard deviation of the small data set

iv) Calculate the confidence interval of the data set at a 95 confidence level

v) Explain in your own words what the confidence interval calculated in (vi)

means (8)

d) The following curves A and B represent two data sets for an analyte in the same sample

analyzed by two different analysts

1

BA

Which data set is the more precise A or B Explain (3)

OUESTION2

a) Explain what is meant by standardization in titration and give one example of a primary

standard used in acid-base titration to standardize Hel and one to standardize NaOH (4)

b) In the determination of chlorine by Fajans titration in samples

i) Name the common adsorption indicator used in this titration (2)

ii) What is the reason for the addition of dextrin before titration (2)

c) You need to produce 500 mL of an aqueous solution in which the concentration 2+ 2+

of Pb is 10 ppm Your source of Pb ions is lead (II) nitrate How much lead

(II) nitrate do you need to weigh out to produce this solution (3)

d)

i) Find the pH in the titration of25 mL of 03 M HF with 03 M NaOH after adding

10 mL of NaOH (5)

ii) What name is given to the resultant solution in b (i) (2)

e) The standard hydrogen electrode (SHE) is the electrode against which all electrode

potentials are referenced

2

i) Draw the SHE and label all components What is the role for the platinum Why

is it a suitable metal for this role (3)

ii) What specifications should be met by the SHE (2)

iii) State the function of the salt bridge and explain how it works (2)

QUESTION 3

a) A young scientist determined the amount of Riboflavin (Vitamin B 2) in a cereal

sample by measuring its fluorescence intensity in 5 acetic acid solution A

calibration curve was prepared by measuring the fluorescence intensitiesrDf a series of

standards of increasing concentrations The concentration of the standard was found

to be 100 ppm Explain in detail TWO ways which the young scientists can use to show that the method and instrument used for measurements gives accurate results

(Give a detailed explanation how this would be achieved) (5)

b) An enzymatic method for determining alcohol in wine is evaluated by comparison

with gas-chromatographic (GC) method The sample is analysed several times by both

methods with the following results ( ethanol)

Enzymatic Method 131 127 126 133 133

GC Method 135 133 130 129

Does the enzymatic method give the same value as the GC method at the 95

confidence level (5)

c) One of the challenges in the quantification of elements is the problem of

interferences Explain what is meant by interferences giving a specific example and a

solution on how this interference can be eliminated in analytical chemistry (4)

d) A standard method for the determination of carbon monoxide (CO) level in gaseous

mixtures is known from many hundred measurements to have a standard deviation of

021 ppm CO A modification of the method yields a value for s ofO15ppm CO

pooled from data set with 12 degrees of freedom Does the modification give more

precise measurements than the original method (5)

3

e) An atomic absorption method for the determination of copper content in fuels yielded

a pooled standard deviation of spooled == 032 jlg CulmL (s ~ 0) The analysis ofthe

oil from a reciprocating aircraft engine showed a copper content of 853 Jg CulmL

i) Calculate the 99 confidence limits for the result based on a mean of four (4)

analyses (3)

ii) How many replicate measurements are necessary to decrease the 99

confidence for the analysis to plusmn 020 Jg CulmL (3)

QUESTION 4

a) The amount of iron (Fe) in drinking water was determined using the standard addition

method The concentration of the Fe standard was 111 ppm The dilutions and signals

for the different dilutions are given in the table below Calculate the amount of Fe in

the water sample in ppb

Sample Volume

(mL)

Standard Volume

(mL) Signal (V)

10 0 0215 10 5 0424 10 10 0685 10 15 0826 10 20 0967

Note All solutions were diluted to a fmal volume of 50 mL (7)

b) External calibration is one other method which can be used in the determination of

iron in water Explain in detail how external calibration differs from standard addition

and also give the main advantage of using standard addition over external calibration

(5)

4

c) Explain two disadvantages of using the standard addition method (3)

d) Internal calibration is another method ofcalibration which is used in determination of

the concentrations of unknown In detail explain the principle of internal standard

explain the advantage of using this type of method over the external calibration and

standard addition (7)

e) Give the three (3) properties which an internal standard should meet (3)

QUESTIONS

a) The CO in a 203 L sample of gas was converted to C02 by passing the gas over

iodine pentoxide heated to ISO degrees Celsius

hOs (s) + SCO (g) -4 SC02 (g) + h (g)

The iodine was distilled at this temperature and was collected in an absorber containing 82S

mL ofO01101 M Na2S203

h (g) + 2S20l- (aq) -4 2r (aq) + S40 (aq)

The excess Na2S203 was back titrated with 216 mL of 000947 M h solution

i) Calculate the concentration in milligrams of CO (2801 gmol) per litre of sample

(S)

ii) The method used in a(i) is known as back titration explain what is meant by back

titration (2)

iii) Give four (4) purposes of back titration ie cases which would require the use of

back titration instead ofdirect titration (4)

b) In titrimetry

i) Differentiate between primary standard and a secondary standard for

titrimetric analysis (2)

ii) Give four (4) desirable properties for a primary standard used for titration

purposes (4)

c) Titration Curves describe how pH changes during various acid-base titrations Draw

the titration curve for the titration of2S mL HCI of 0100 M with O1OOM HCl (S)

5

d) Using sketch diagrams explain what would be the difference ofa titration curve

obtained when 10 mL 01 M acetic acid is titrated with 01 M sodium hydroxide from

that of 01 M hydrochloric acid titrated with 01 M sodium hydroxide (Do not

Calculate) (3)

QUESTION 6

a) One of the properties of a homogeneous precipitate in gravimetry is that it has fewer

impurities Describe the (2) ways which can be used in the formation ofa

homogeneous precipitate Give an example for each (4)

b) Explain how the particle size of a precipitate can be controlled WIth reference to If

relative supersaturation (3)

c) i) What is meant by digestion ofa precipitate Briefly describe what happens in the

process of digesting a precipitate and give Q(2) advantages of this step during

gravimetric analysis (3)

ii) What is peptization Howcan this phenomenon be avoided during gravimetric

analysis (2)

d) One of the gravimetric titration methods used in analytical chemistry is the Volhard

titration

i) Describe the Volhard titration method What is this type of titration used for

(3)

ii) Give the two main challenges encountered when using this method of

titration (2)

iii) How can these problems listed in b(ii) be solved (2)

e) A 02356g sample containing only NaCI and BaCl2 Yielded 04637 g of dried Ag CI

on adding AgN03 to the sample Calculate the percent of each halogen compound in

the sample (6)

6

APPENDIX

bull VALUES OF tFOR VARIOUS LEVELS OF PROBABILITY

Number of Factor for Confidence Interval Observations

- 00~95 99~ 1 308 631 127 637

2 189 292 43 992 316

3_ 164 235 318 584 129

4shy -shy 153 213 278 46 86

5 148 202 257 403 686 ~

6 144 194 245 371 596

7 142 19 236 35 54

8 14 1 Qt I ~1 336 504

9 138 183 226 325 478

10 137 181 223 317 459

11 136 18 22 311 444

12 136 178 218 306 432

13 135 177 216 301 422

14 134 176 214 298 414

i CRITICAL VALUES FOR REJECITON QUOTIENT Q 1

Number of 1 90 95 ~I Icnnflrlpnr-p IIIObservations I Confidence Confidence I Confidence I

i 3 0941 0970 lit 09941 i shy

4 0765 0829t ~----__~rl________i________l~__0_9_2_6~r-5 1 0642 0710 0821 r_I

r----6-----rl---o-56-o---r--o-6-25---~1--0-7-4-0--r_

~----7----_~--0-50-7---r__0-5-68--~1--0-6-8-0--r-1 8 0468 0526 1 0634 r_l

~___9 ____li___0_~_7___lr__0_4_9_3_middot_rl__0_5_9_8__r_l

10 0412 0466 0568I I

Confidence Levels for Various Values middotofz

Confidence Level J z

-50

68 i

8amp

067

100

128

I

I I

shy

90

-

164

95 196

954 200

99 258

997 300

999 329

Degrees of Derees offreedom for 5J 1rledom

7 s III f

furl Z ) if 5 Ci ) 10 15 20 pO jQgt

1 190 192 l lQ2 193 193 1~41194 HU lQ4 liU 1M 194 195 195 3 9_~5 9211 i 912 WI 1194 iU9 IlP4 lUI 1179 874 Pi) RM I IUil 853 4 694 659 r 639 626 616 609 604 600 596 591 586 580 ~ 575 563 S 579 HI 519 505 495 4881 482 477 474 46-~ 462 456 i 450 436

6 Sl4 476 53 4J9 41S 421 4lS 41Q 406 400 394 181 1381 367

bull~ 414 435 412 gt97 387 379 373 368 164 353 351 ~A4 i 138 323 8 446 407 384 369 358 350 344 339 335 32S 122 31S i 308 293

9 426 186 )() 348 JJ7 129 323 3l8 314 3U7 lUl 294 I 286 271 Hl f-lt-4IO 371 l 343 333 3~ 314 301 Hi 293 291 284shy 271 2711 bull 254-__- _--_ _- I-shy --shy ---shy --_ - -~r-middot---middot middot __shyII 398 359 ~ 336 320 310 301 295 290 285 279 272 265 257 240- 2S4111 38 349 126 II 300 291 28S 280 275 260) 162 247 23(1

1 HI )41 i ItA Hi 1 92 Ul li7 lil -67 2M -~t -4Q 2 I~ 14 374 334 bull 311 296 21 276 270 16$ ltiO 251 246 239 [ 131 213 15 J()~ 3l~ 3Jl6 2Kl 271) 271 L2~ 159 254 24-~ 240 ali 225 ---shy -16 l6 324 1111 285 274 Vi( 2jil 250 249 242shy 2Ji 22R I 219 201 ]7 3J9 3W 296 281 270 261 255 249 245 23~ ln un Hi 196

219 t18 ~_6 SII) 293 11 2fi6 ]8 151 246 241 234 217 211 192 19 35 lnf 290 274 263 254shy l48 242 238 231 223 216 I201 188 20 349 lLO t 2$1 271 260 251 245 239 235 22~ 220 212 204 184 30 332 292 269 253 242 233 221 221 116 209 201 193 JS4 162 0 300 260 lJ7 221 lJO 201 194 1amp8 U3 J7~ 167 157 14( 100

USEFUL CONSTANTS

Ka Acid Base Name Formula Formula Name

Large Perchloric acid HCI04 CI04shy Perchlorate ion 32 10~ Hydroiodic acid HI 1shy Iodide 10 10~ Hydrobromic acid HBr Br- Bromide 13 lOb Hydrochloric acid HCI CI- Chloride 10 103 Sulfuric acid H2SO4 HS04shy Hydrogen sulfate ion 24 101

-Nitric acid RN03 N03shy Nitrate ion

-------shy Hydronium ion H3O+ H2O Water

~

Ka shy- - Acid Conjugate Base

Name Formula Formula Name Large -

Perchloric acid HCI04 CI04shy Perchlorate ion 32 10~ Hydroiodic acid HI 1shy Iodide 10 109 Hydrobromic acid HBr Br- Bromide 13 lOb Hydrochloric acid HCI CI- Chloride 10103 Sulfuric acid H2SO4 HS04shy Hydrogen sulfate ion 24 101 Nitric acid HN03 N03shy II Nitrate ion -------shy Hydronium ion H3O+ H2O Water

54 1O-l Oxalic acid H02C20 2H H02C20 2shy Hydrogen oxalate ion 13 1O-l Sulfurous acid H2S03 HS03shy Hydrogen sulfite ion 10 10-2 Hydrogen sulfate ion HS04shy S04 2- Sulfate ion 71 10-3 Phosphoric acid H3P04 H2P04- Dihydrogen phosphate

ion 72 10-4 Nitrous acid HN02 N03shy Nitrite ion 66 10-4 Hydrofluoric acid HF F- Fluoride ion 18 10-4 Methanoic acid HC02H HC02shy Methanoate ion 63 10- Benzoic acid C6HsCOOH C6HsCOOshy Benzoate ion 54 10- Hydrogen oxalate ion H02C20~- 02C20 2 ~- Oxalate ion 18 10- Ethanoic acid CH3COOH CH3COO Ethanoate (acetate)

ion 44 10- 1 Carbonic acid C03lshy HC03shy Hydrogen carbonate

ion 11 10-7 Hydrosulfuric acid H2S HS- Hydrogen sulfide ion 63 1O-~ Dihydrogen phosphate

ion H2P04shy HP04l- Hydrogen phosphate

ion 62 10-8 Hydrogen sulfite ion -lISshy S2shy Sulfite ion 29 10-~ Hypochlorous acid HCIO CIO- Hypochlorite ion 62 10-10 Hydrocyanic acid HCN CN- Cyanide ion 58 lO- IU Ammonium ion NH4 + NH3 Ammonia 58 10-10 Boric acid H3B03 H2Bq3 - Dihydrogen carbonate

ion 47 10-11 Hydrogen carbonate ion HC03shy C03 l- Carbonate ion 42 lO- lJ

Hydrogen phosphate ion

HP04lshy P04-shy Phosphate ion

18 10-13 Dihydrogen borate ion H2B03- HB03l- Hydrogen borate ion 13 10-1- Hydrogen sulfide ion HSshy S ~- Sulfide ion 16 10-14 Hydrogen borate ion HB03

2- B033shy Borate ion --------shy water H2O OH- Hydroxide

I

j 4

-f

I to

Ouantil Symbol r

Speed of lighr c Elemlfmary e

charge

Faraday F=eNI COMstanc

BoltzrTinn k cons3Ct

Gas costant n=kNA

PlancK constant h

h-h2T Avogadro Ni

constant

Atomic mass u unit

Mass of Iectron m proton m neutron m

Vacuum 1 permeabilityt

VaCtum r-lrrpopermittivity

tiro Bohr magneton ]I efl2m Nuclear

IN - en2mmagneton electron g

~value

Schr radius 2 4vm ( Rydber R ml4Shl c

constant

Fine nrucure C= Jloeh2hconstant

Gravitational G ccnSlant

tStandard gIIccelerinion ot free alit

f p n m

femto pico nano micro 10- 1S 10-111 10- 10-middot

Value General data and 2s97 9~42 x 10a m 5- 1 fundamental 160217T)lt) 0-111 C constantsmiddot

S64aS x 10 C mol-I

138066 X 10-1 J Kshy

83451 J 1(-1 mol-I

820578 x 10-2 cm1 atm 1(-1 mol-

62364 L TQrr 1(-1 mol

6526 as x 10---)1 J s

105457)c 10-)1 J oS 602214 x 1012 mol-I

1660 54 x 10-z kg

9109351 x 10-11 kg

167262 X 10-zr kg

middot167493 x Omiddotzr kg

4Jr Xmiddot 0-- J r C-2 m-r 4nx lomiddot7 T2J- ml

B8S4 19 X10-12J~1 C2 m-1

126Sx 1c-tG rIC2m-1

927402 x 10-10amp J T- SOSO 79 x 1o-zrJ I~

2C02~2

529~77 X 10-11 m

1091 37x 10cm-

7297 isx 10-3

65725S x la-II N m Zlcg-Z

bull aSOS 65Jil-~

r Exct Idilo Vllu

c d M G Prefixes deci kilo mega glgl

10-1 10 10middot 105

QUESTION 1

a) Define or explain the following

i) Accuracy

ii) Determinate error

iii) Precision

iv) Indeterminate error (4)

b) i) List the four main types ofdeterminate error (2)

ii) Give a brief explanationdescription of each of the types of determinate error you listed in

(i) (4)

iii) Explain two ways which can be used to detect determinate errors (A-)

c) The following data were obtained for the analysis of a standard soil sample containing

the analyte acenaphthene a known carcinogen The concentration ofacenaphthene

in the sample is given as 32 ppb

Determination Acenaphthene (Ppb)

1 30

2 29

3 31

i) Calculate the mean of the data set

ii) Calculate the relative error of the mean of the data set

iii) Calculate the standard deviation of the small data set

iv) Calculate the confidence interval of the data set at a 95 confidence level

v) Explain in your own words what the confidence interval calculated in (vi)

means (8)

d) The following curves A and B represent two data sets for an analyte in the same sample

analyzed by two different analysts

1

BA

Which data set is the more precise A or B Explain (3)

OUESTION2

a) Explain what is meant by standardization in titration and give one example of a primary

standard used in acid-base titration to standardize Hel and one to standardize NaOH (4)

b) In the determination of chlorine by Fajans titration in samples

i) Name the common adsorption indicator used in this titration (2)

ii) What is the reason for the addition of dextrin before titration (2)

c) You need to produce 500 mL of an aqueous solution in which the concentration 2+ 2+

of Pb is 10 ppm Your source of Pb ions is lead (II) nitrate How much lead

(II) nitrate do you need to weigh out to produce this solution (3)

d)

i) Find the pH in the titration of25 mL of 03 M HF with 03 M NaOH after adding

10 mL of NaOH (5)

ii) What name is given to the resultant solution in b (i) (2)

e) The standard hydrogen electrode (SHE) is the electrode against which all electrode

potentials are referenced

2

i) Draw the SHE and label all components What is the role for the platinum Why

is it a suitable metal for this role (3)

ii) What specifications should be met by the SHE (2)

iii) State the function of the salt bridge and explain how it works (2)

QUESTION 3

a) A young scientist determined the amount of Riboflavin (Vitamin B 2) in a cereal

sample by measuring its fluorescence intensity in 5 acetic acid solution A

calibration curve was prepared by measuring the fluorescence intensitiesrDf a series of

standards of increasing concentrations The concentration of the standard was found

to be 100 ppm Explain in detail TWO ways which the young scientists can use to show that the method and instrument used for measurements gives accurate results

(Give a detailed explanation how this would be achieved) (5)

b) An enzymatic method for determining alcohol in wine is evaluated by comparison

with gas-chromatographic (GC) method The sample is analysed several times by both

methods with the following results ( ethanol)

Enzymatic Method 131 127 126 133 133

GC Method 135 133 130 129

Does the enzymatic method give the same value as the GC method at the 95

confidence level (5)

c) One of the challenges in the quantification of elements is the problem of

interferences Explain what is meant by interferences giving a specific example and a

solution on how this interference can be eliminated in analytical chemistry (4)

d) A standard method for the determination of carbon monoxide (CO) level in gaseous

mixtures is known from many hundred measurements to have a standard deviation of

021 ppm CO A modification of the method yields a value for s ofO15ppm CO

pooled from data set with 12 degrees of freedom Does the modification give more

precise measurements than the original method (5)

3

e) An atomic absorption method for the determination of copper content in fuels yielded

a pooled standard deviation of spooled == 032 jlg CulmL (s ~ 0) The analysis ofthe

oil from a reciprocating aircraft engine showed a copper content of 853 Jg CulmL

i) Calculate the 99 confidence limits for the result based on a mean of four (4)

analyses (3)

ii) How many replicate measurements are necessary to decrease the 99

confidence for the analysis to plusmn 020 Jg CulmL (3)

QUESTION 4

a) The amount of iron (Fe) in drinking water was determined using the standard addition

method The concentration of the Fe standard was 111 ppm The dilutions and signals

for the different dilutions are given in the table below Calculate the amount of Fe in

the water sample in ppb

Sample Volume

(mL)

Standard Volume

(mL) Signal (V)

10 0 0215 10 5 0424 10 10 0685 10 15 0826 10 20 0967

Note All solutions were diluted to a fmal volume of 50 mL (7)

b) External calibration is one other method which can be used in the determination of

iron in water Explain in detail how external calibration differs from standard addition

and also give the main advantage of using standard addition over external calibration

(5)

4

c) Explain two disadvantages of using the standard addition method (3)

d) Internal calibration is another method ofcalibration which is used in determination of

the concentrations of unknown In detail explain the principle of internal standard

explain the advantage of using this type of method over the external calibration and

standard addition (7)

e) Give the three (3) properties which an internal standard should meet (3)

QUESTIONS

a) The CO in a 203 L sample of gas was converted to C02 by passing the gas over

iodine pentoxide heated to ISO degrees Celsius

hOs (s) + SCO (g) -4 SC02 (g) + h (g)

The iodine was distilled at this temperature and was collected in an absorber containing 82S

mL ofO01101 M Na2S203

h (g) + 2S20l- (aq) -4 2r (aq) + S40 (aq)

The excess Na2S203 was back titrated with 216 mL of 000947 M h solution

i) Calculate the concentration in milligrams of CO (2801 gmol) per litre of sample

(S)

ii) The method used in a(i) is known as back titration explain what is meant by back

titration (2)

iii) Give four (4) purposes of back titration ie cases which would require the use of

back titration instead ofdirect titration (4)

b) In titrimetry

i) Differentiate between primary standard and a secondary standard for

titrimetric analysis (2)

ii) Give four (4) desirable properties for a primary standard used for titration

purposes (4)

c) Titration Curves describe how pH changes during various acid-base titrations Draw

the titration curve for the titration of2S mL HCI of 0100 M with O1OOM HCl (S)

5

d) Using sketch diagrams explain what would be the difference ofa titration curve

obtained when 10 mL 01 M acetic acid is titrated with 01 M sodium hydroxide from

that of 01 M hydrochloric acid titrated with 01 M sodium hydroxide (Do not

Calculate) (3)

QUESTION 6

a) One of the properties of a homogeneous precipitate in gravimetry is that it has fewer

impurities Describe the (2) ways which can be used in the formation ofa

homogeneous precipitate Give an example for each (4)

b) Explain how the particle size of a precipitate can be controlled WIth reference to If

relative supersaturation (3)

c) i) What is meant by digestion ofa precipitate Briefly describe what happens in the

process of digesting a precipitate and give Q(2) advantages of this step during

gravimetric analysis (3)

ii) What is peptization Howcan this phenomenon be avoided during gravimetric

analysis (2)

d) One of the gravimetric titration methods used in analytical chemistry is the Volhard

titration

i) Describe the Volhard titration method What is this type of titration used for

(3)

ii) Give the two main challenges encountered when using this method of

titration (2)

iii) How can these problems listed in b(ii) be solved (2)

e) A 02356g sample containing only NaCI and BaCl2 Yielded 04637 g of dried Ag CI

on adding AgN03 to the sample Calculate the percent of each halogen compound in

the sample (6)

6

APPENDIX

bull VALUES OF tFOR VARIOUS LEVELS OF PROBABILITY

Number of Factor for Confidence Interval Observations

- 00~95 99~ 1 308 631 127 637

2 189 292 43 992 316

3_ 164 235 318 584 129

4shy -shy 153 213 278 46 86

5 148 202 257 403 686 ~

6 144 194 245 371 596

7 142 19 236 35 54

8 14 1 Qt I ~1 336 504

9 138 183 226 325 478

10 137 181 223 317 459

11 136 18 22 311 444

12 136 178 218 306 432

13 135 177 216 301 422

14 134 176 214 298 414

i CRITICAL VALUES FOR REJECITON QUOTIENT Q 1

Number of 1 90 95 ~I Icnnflrlpnr-p IIIObservations I Confidence Confidence I Confidence I

i 3 0941 0970 lit 09941 i shy

4 0765 0829t ~----__~rl________i________l~__0_9_2_6~r-5 1 0642 0710 0821 r_I

r----6-----rl---o-56-o---r--o-6-25---~1--0-7-4-0--r_

~----7----_~--0-50-7---r__0-5-68--~1--0-6-8-0--r-1 8 0468 0526 1 0634 r_l

~___9 ____li___0_~_7___lr__0_4_9_3_middot_rl__0_5_9_8__r_l

10 0412 0466 0568I I

Confidence Levels for Various Values middotofz

Confidence Level J z

-50

68 i

8amp

067

100

128

I

I I

shy

90

-

164

95 196

954 200

99 258

997 300

999 329

Degrees of Derees offreedom for 5J 1rledom

7 s III f

furl Z ) if 5 Ci ) 10 15 20 pO jQgt

1 190 192 l lQ2 193 193 1~41194 HU lQ4 liU 1M 194 195 195 3 9_~5 9211 i 912 WI 1194 iU9 IlP4 lUI 1179 874 Pi) RM I IUil 853 4 694 659 r 639 626 616 609 604 600 596 591 586 580 ~ 575 563 S 579 HI 519 505 495 4881 482 477 474 46-~ 462 456 i 450 436

6 Sl4 476 53 4J9 41S 421 4lS 41Q 406 400 394 181 1381 367

bull~ 414 435 412 gt97 387 379 373 368 164 353 351 ~A4 i 138 323 8 446 407 384 369 358 350 344 339 335 32S 122 31S i 308 293

9 426 186 )() 348 JJ7 129 323 3l8 314 3U7 lUl 294 I 286 271 Hl f-lt-4IO 371 l 343 333 3~ 314 301 Hi 293 291 284shy 271 2711 bull 254-__- _--_ _- I-shy --shy ---shy --_ - -~r-middot---middot middot __shyII 398 359 ~ 336 320 310 301 295 290 285 279 272 265 257 240- 2S4111 38 349 126 II 300 291 28S 280 275 260) 162 247 23(1

1 HI )41 i ItA Hi 1 92 Ul li7 lil -67 2M -~t -4Q 2 I~ 14 374 334 bull 311 296 21 276 270 16$ ltiO 251 246 239 [ 131 213 15 J()~ 3l~ 3Jl6 2Kl 271) 271 L2~ 159 254 24-~ 240 ali 225 ---shy -16 l6 324 1111 285 274 Vi( 2jil 250 249 242shy 2Ji 22R I 219 201 ]7 3J9 3W 296 281 270 261 255 249 245 23~ ln un Hi 196

219 t18 ~_6 SII) 293 11 2fi6 ]8 151 246 241 234 217 211 192 19 35 lnf 290 274 263 254shy l48 242 238 231 223 216 I201 188 20 349 lLO t 2$1 271 260 251 245 239 235 22~ 220 212 204 184 30 332 292 269 253 242 233 221 221 116 209 201 193 JS4 162 0 300 260 lJ7 221 lJO 201 194 1amp8 U3 J7~ 167 157 14( 100

USEFUL CONSTANTS

Ka Acid Base Name Formula Formula Name

Large Perchloric acid HCI04 CI04shy Perchlorate ion 32 10~ Hydroiodic acid HI 1shy Iodide 10 10~ Hydrobromic acid HBr Br- Bromide 13 lOb Hydrochloric acid HCI CI- Chloride 10 103 Sulfuric acid H2SO4 HS04shy Hydrogen sulfate ion 24 101

-Nitric acid RN03 N03shy Nitrate ion

-------shy Hydronium ion H3O+ H2O Water

~

Ka shy- - Acid Conjugate Base

Name Formula Formula Name Large -

Perchloric acid HCI04 CI04shy Perchlorate ion 32 10~ Hydroiodic acid HI 1shy Iodide 10 109 Hydrobromic acid HBr Br- Bromide 13 lOb Hydrochloric acid HCI CI- Chloride 10103 Sulfuric acid H2SO4 HS04shy Hydrogen sulfate ion 24 101 Nitric acid HN03 N03shy II Nitrate ion -------shy Hydronium ion H3O+ H2O Water

54 1O-l Oxalic acid H02C20 2H H02C20 2shy Hydrogen oxalate ion 13 1O-l Sulfurous acid H2S03 HS03shy Hydrogen sulfite ion 10 10-2 Hydrogen sulfate ion HS04shy S04 2- Sulfate ion 71 10-3 Phosphoric acid H3P04 H2P04- Dihydrogen phosphate

ion 72 10-4 Nitrous acid HN02 N03shy Nitrite ion 66 10-4 Hydrofluoric acid HF F- Fluoride ion 18 10-4 Methanoic acid HC02H HC02shy Methanoate ion 63 10- Benzoic acid C6HsCOOH C6HsCOOshy Benzoate ion 54 10- Hydrogen oxalate ion H02C20~- 02C20 2 ~- Oxalate ion 18 10- Ethanoic acid CH3COOH CH3COO Ethanoate (acetate)

ion 44 10- 1 Carbonic acid C03lshy HC03shy Hydrogen carbonate

ion 11 10-7 Hydrosulfuric acid H2S HS- Hydrogen sulfide ion 63 1O-~ Dihydrogen phosphate

ion H2P04shy HP04l- Hydrogen phosphate

ion 62 10-8 Hydrogen sulfite ion -lISshy S2shy Sulfite ion 29 10-~ Hypochlorous acid HCIO CIO- Hypochlorite ion 62 10-10 Hydrocyanic acid HCN CN- Cyanide ion 58 lO- IU Ammonium ion NH4 + NH3 Ammonia 58 10-10 Boric acid H3B03 H2Bq3 - Dihydrogen carbonate

ion 47 10-11 Hydrogen carbonate ion HC03shy C03 l- Carbonate ion 42 lO- lJ

Hydrogen phosphate ion

HP04lshy P04-shy Phosphate ion

18 10-13 Dihydrogen borate ion H2B03- HB03l- Hydrogen borate ion 13 10-1- Hydrogen sulfide ion HSshy S ~- Sulfide ion 16 10-14 Hydrogen borate ion HB03

2- B033shy Borate ion --------shy water H2O OH- Hydroxide

I

j 4

-f

I to

Ouantil Symbol r

Speed of lighr c Elemlfmary e

charge

Faraday F=eNI COMstanc

BoltzrTinn k cons3Ct

Gas costant n=kNA

PlancK constant h

h-h2T Avogadro Ni

constant

Atomic mass u unit

Mass of Iectron m proton m neutron m

Vacuum 1 permeabilityt

VaCtum r-lrrpopermittivity

tiro Bohr magneton ]I efl2m Nuclear

IN - en2mmagneton electron g

~value

Schr radius 2 4vm ( Rydber R ml4Shl c

constant

Fine nrucure C= Jloeh2hconstant

Gravitational G ccnSlant

tStandard gIIccelerinion ot free alit

f p n m

femto pico nano micro 10- 1S 10-111 10- 10-middot

Value General data and 2s97 9~42 x 10a m 5- 1 fundamental 160217T)lt) 0-111 C constantsmiddot

S64aS x 10 C mol-I

138066 X 10-1 J Kshy

83451 J 1(-1 mol-I

820578 x 10-2 cm1 atm 1(-1 mol-

62364 L TQrr 1(-1 mol

6526 as x 10---)1 J s

105457)c 10-)1 J oS 602214 x 1012 mol-I

1660 54 x 10-z kg

9109351 x 10-11 kg

167262 X 10-zr kg

middot167493 x Omiddotzr kg

4Jr Xmiddot 0-- J r C-2 m-r 4nx lomiddot7 T2J- ml

B8S4 19 X10-12J~1 C2 m-1

126Sx 1c-tG rIC2m-1

927402 x 10-10amp J T- SOSO 79 x 1o-zrJ I~

2C02~2

529~77 X 10-11 m

1091 37x 10cm-

7297 isx 10-3

65725S x la-II N m Zlcg-Z

bull aSOS 65Jil-~

r Exct Idilo Vllu

c d M G Prefixes deci kilo mega glgl

10-1 10 10middot 105

BA

Which data set is the more precise A or B Explain (3)

OUESTION2

a) Explain what is meant by standardization in titration and give one example of a primary

standard used in acid-base titration to standardize Hel and one to standardize NaOH (4)

b) In the determination of chlorine by Fajans titration in samples

i) Name the common adsorption indicator used in this titration (2)

ii) What is the reason for the addition of dextrin before titration (2)

c) You need to produce 500 mL of an aqueous solution in which the concentration 2+ 2+

of Pb is 10 ppm Your source of Pb ions is lead (II) nitrate How much lead

(II) nitrate do you need to weigh out to produce this solution (3)

d)

i) Find the pH in the titration of25 mL of 03 M HF with 03 M NaOH after adding

10 mL of NaOH (5)

ii) What name is given to the resultant solution in b (i) (2)

e) The standard hydrogen electrode (SHE) is the electrode against which all electrode

potentials are referenced

2

i) Draw the SHE and label all components What is the role for the platinum Why

is it a suitable metal for this role (3)

ii) What specifications should be met by the SHE (2)

iii) State the function of the salt bridge and explain how it works (2)

QUESTION 3

a) A young scientist determined the amount of Riboflavin (Vitamin B 2) in a cereal

sample by measuring its fluorescence intensity in 5 acetic acid solution A

calibration curve was prepared by measuring the fluorescence intensitiesrDf a series of

standards of increasing concentrations The concentration of the standard was found

to be 100 ppm Explain in detail TWO ways which the young scientists can use to show that the method and instrument used for measurements gives accurate results

(Give a detailed explanation how this would be achieved) (5)

b) An enzymatic method for determining alcohol in wine is evaluated by comparison

with gas-chromatographic (GC) method The sample is analysed several times by both

methods with the following results ( ethanol)

Enzymatic Method 131 127 126 133 133

GC Method 135 133 130 129

Does the enzymatic method give the same value as the GC method at the 95

confidence level (5)

c) One of the challenges in the quantification of elements is the problem of

interferences Explain what is meant by interferences giving a specific example and a

solution on how this interference can be eliminated in analytical chemistry (4)

d) A standard method for the determination of carbon monoxide (CO) level in gaseous

mixtures is known from many hundred measurements to have a standard deviation of

021 ppm CO A modification of the method yields a value for s ofO15ppm CO

pooled from data set with 12 degrees of freedom Does the modification give more

precise measurements than the original method (5)

3

e) An atomic absorption method for the determination of copper content in fuels yielded

a pooled standard deviation of spooled == 032 jlg CulmL (s ~ 0) The analysis ofthe

oil from a reciprocating aircraft engine showed a copper content of 853 Jg CulmL

i) Calculate the 99 confidence limits for the result based on a mean of four (4)

analyses (3)

ii) How many replicate measurements are necessary to decrease the 99

confidence for the analysis to plusmn 020 Jg CulmL (3)

QUESTION 4

a) The amount of iron (Fe) in drinking water was determined using the standard addition

method The concentration of the Fe standard was 111 ppm The dilutions and signals

for the different dilutions are given in the table below Calculate the amount of Fe in

the water sample in ppb

Sample Volume

(mL)

Standard Volume

(mL) Signal (V)

10 0 0215 10 5 0424 10 10 0685 10 15 0826 10 20 0967

Note All solutions were diluted to a fmal volume of 50 mL (7)

b) External calibration is one other method which can be used in the determination of

iron in water Explain in detail how external calibration differs from standard addition

and also give the main advantage of using standard addition over external calibration

(5)

4

c) Explain two disadvantages of using the standard addition method (3)

d) Internal calibration is another method ofcalibration which is used in determination of

the concentrations of unknown In detail explain the principle of internal standard

explain the advantage of using this type of method over the external calibration and

standard addition (7)

e) Give the three (3) properties which an internal standard should meet (3)

QUESTIONS

a) The CO in a 203 L sample of gas was converted to C02 by passing the gas over

iodine pentoxide heated to ISO degrees Celsius

hOs (s) + SCO (g) -4 SC02 (g) + h (g)

The iodine was distilled at this temperature and was collected in an absorber containing 82S

mL ofO01101 M Na2S203

h (g) + 2S20l- (aq) -4 2r (aq) + S40 (aq)

The excess Na2S203 was back titrated with 216 mL of 000947 M h solution

i) Calculate the concentration in milligrams of CO (2801 gmol) per litre of sample

(S)

ii) The method used in a(i) is known as back titration explain what is meant by back

titration (2)

iii) Give four (4) purposes of back titration ie cases which would require the use of

back titration instead ofdirect titration (4)

b) In titrimetry

i) Differentiate between primary standard and a secondary standard for

titrimetric analysis (2)

ii) Give four (4) desirable properties for a primary standard used for titration

purposes (4)

c) Titration Curves describe how pH changes during various acid-base titrations Draw

the titration curve for the titration of2S mL HCI of 0100 M with O1OOM HCl (S)

5

d) Using sketch diagrams explain what would be the difference ofa titration curve

obtained when 10 mL 01 M acetic acid is titrated with 01 M sodium hydroxide from

that of 01 M hydrochloric acid titrated with 01 M sodium hydroxide (Do not

Calculate) (3)

QUESTION 6

a) One of the properties of a homogeneous precipitate in gravimetry is that it has fewer

impurities Describe the (2) ways which can be used in the formation ofa

homogeneous precipitate Give an example for each (4)

b) Explain how the particle size of a precipitate can be controlled WIth reference to If

relative supersaturation (3)

c) i) What is meant by digestion ofa precipitate Briefly describe what happens in the

process of digesting a precipitate and give Q(2) advantages of this step during

gravimetric analysis (3)

ii) What is peptization Howcan this phenomenon be avoided during gravimetric

analysis (2)

d) One of the gravimetric titration methods used in analytical chemistry is the Volhard

titration

i) Describe the Volhard titration method What is this type of titration used for

(3)

ii) Give the two main challenges encountered when using this method of

titration (2)

iii) How can these problems listed in b(ii) be solved (2)

e) A 02356g sample containing only NaCI and BaCl2 Yielded 04637 g of dried Ag CI

on adding AgN03 to the sample Calculate the percent of each halogen compound in

the sample (6)

6

APPENDIX

bull VALUES OF tFOR VARIOUS LEVELS OF PROBABILITY

Number of Factor for Confidence Interval Observations

- 00~95 99~ 1 308 631 127 637

2 189 292 43 992 316

3_ 164 235 318 584 129

4shy -shy 153 213 278 46 86

5 148 202 257 403 686 ~

6 144 194 245 371 596

7 142 19 236 35 54

8 14 1 Qt I ~1 336 504

9 138 183 226 325 478

10 137 181 223 317 459

11 136 18 22 311 444

12 136 178 218 306 432

13 135 177 216 301 422

14 134 176 214 298 414

i CRITICAL VALUES FOR REJECITON QUOTIENT Q 1

Number of 1 90 95 ~I Icnnflrlpnr-p IIIObservations I Confidence Confidence I Confidence I

i 3 0941 0970 lit 09941 i shy

4 0765 0829t ~----__~rl________i________l~__0_9_2_6~r-5 1 0642 0710 0821 r_I

r----6-----rl---o-56-o---r--o-6-25---~1--0-7-4-0--r_

~----7----_~--0-50-7---r__0-5-68--~1--0-6-8-0--r-1 8 0468 0526 1 0634 r_l

~___9 ____li___0_~_7___lr__0_4_9_3_middot_rl__0_5_9_8__r_l

10 0412 0466 0568I I

Confidence Levels for Various Values middotofz

Confidence Level J z

-50

68 i

8amp

067

100

128

I

I I

shy

90

-

164

95 196

954 200

99 258

997 300

999 329

Degrees of Derees offreedom for 5J 1rledom

7 s III f

furl Z ) if 5 Ci ) 10 15 20 pO jQgt

1 190 192 l lQ2 193 193 1~41194 HU lQ4 liU 1M 194 195 195 3 9_~5 9211 i 912 WI 1194 iU9 IlP4 lUI 1179 874 Pi) RM I IUil 853 4 694 659 r 639 626 616 609 604 600 596 591 586 580 ~ 575 563 S 579 HI 519 505 495 4881 482 477 474 46-~ 462 456 i 450 436

6 Sl4 476 53 4J9 41S 421 4lS 41Q 406 400 394 181 1381 367

bull~ 414 435 412 gt97 387 379 373 368 164 353 351 ~A4 i 138 323 8 446 407 384 369 358 350 344 339 335 32S 122 31S i 308 293

9 426 186 )() 348 JJ7 129 323 3l8 314 3U7 lUl 294 I 286 271 Hl f-lt-4IO 371 l 343 333 3~ 314 301 Hi 293 291 284shy 271 2711 bull 254-__- _--_ _- I-shy --shy ---shy --_ - -~r-middot---middot middot __shyII 398 359 ~ 336 320 310 301 295 290 285 279 272 265 257 240- 2S4111 38 349 126 II 300 291 28S 280 275 260) 162 247 23(1

1 HI )41 i ItA Hi 1 92 Ul li7 lil -67 2M -~t -4Q 2 I~ 14 374 334 bull 311 296 21 276 270 16$ ltiO 251 246 239 [ 131 213 15 J()~ 3l~ 3Jl6 2Kl 271) 271 L2~ 159 254 24-~ 240 ali 225 ---shy -16 l6 324 1111 285 274 Vi( 2jil 250 249 242shy 2Ji 22R I 219 201 ]7 3J9 3W 296 281 270 261 255 249 245 23~ ln un Hi 196

219 t18 ~_6 SII) 293 11 2fi6 ]8 151 246 241 234 217 211 192 19 35 lnf 290 274 263 254shy l48 242 238 231 223 216 I201 188 20 349 lLO t 2$1 271 260 251 245 239 235 22~ 220 212 204 184 30 332 292 269 253 242 233 221 221 116 209 201 193 JS4 162 0 300 260 lJ7 221 lJO 201 194 1amp8 U3 J7~ 167 157 14( 100

USEFUL CONSTANTS

Ka Acid Base Name Formula Formula Name

Large Perchloric acid HCI04 CI04shy Perchlorate ion 32 10~ Hydroiodic acid HI 1shy Iodide 10 10~ Hydrobromic acid HBr Br- Bromide 13 lOb Hydrochloric acid HCI CI- Chloride 10 103 Sulfuric acid H2SO4 HS04shy Hydrogen sulfate ion 24 101

-Nitric acid RN03 N03shy Nitrate ion

-------shy Hydronium ion H3O+ H2O Water

~

Ka shy- - Acid Conjugate Base

Name Formula Formula Name Large -

Perchloric acid HCI04 CI04shy Perchlorate ion 32 10~ Hydroiodic acid HI 1shy Iodide 10 109 Hydrobromic acid HBr Br- Bromide 13 lOb Hydrochloric acid HCI CI- Chloride 10103 Sulfuric acid H2SO4 HS04shy Hydrogen sulfate ion 24 101 Nitric acid HN03 N03shy II Nitrate ion -------shy Hydronium ion H3O+ H2O Water

54 1O-l Oxalic acid H02C20 2H H02C20 2shy Hydrogen oxalate ion 13 1O-l Sulfurous acid H2S03 HS03shy Hydrogen sulfite ion 10 10-2 Hydrogen sulfate ion HS04shy S04 2- Sulfate ion 71 10-3 Phosphoric acid H3P04 H2P04- Dihydrogen phosphate

ion 72 10-4 Nitrous acid HN02 N03shy Nitrite ion 66 10-4 Hydrofluoric acid HF F- Fluoride ion 18 10-4 Methanoic acid HC02H HC02shy Methanoate ion 63 10- Benzoic acid C6HsCOOH C6HsCOOshy Benzoate ion 54 10- Hydrogen oxalate ion H02C20~- 02C20 2 ~- Oxalate ion 18 10- Ethanoic acid CH3COOH CH3COO Ethanoate (acetate)

ion 44 10- 1 Carbonic acid C03lshy HC03shy Hydrogen carbonate

ion 11 10-7 Hydrosulfuric acid H2S HS- Hydrogen sulfide ion 63 1O-~ Dihydrogen phosphate

ion H2P04shy HP04l- Hydrogen phosphate

ion 62 10-8 Hydrogen sulfite ion -lISshy S2shy Sulfite ion 29 10-~ Hypochlorous acid HCIO CIO- Hypochlorite ion 62 10-10 Hydrocyanic acid HCN CN- Cyanide ion 58 lO- IU Ammonium ion NH4 + NH3 Ammonia 58 10-10 Boric acid H3B03 H2Bq3 - Dihydrogen carbonate

ion 47 10-11 Hydrogen carbonate ion HC03shy C03 l- Carbonate ion 42 lO- lJ

Hydrogen phosphate ion

HP04lshy P04-shy Phosphate ion

18 10-13 Dihydrogen borate ion H2B03- HB03l- Hydrogen borate ion 13 10-1- Hydrogen sulfide ion HSshy S ~- Sulfide ion 16 10-14 Hydrogen borate ion HB03

2- B033shy Borate ion --------shy water H2O OH- Hydroxide

I

j 4

-f

I to

Ouantil Symbol r

Speed of lighr c Elemlfmary e

charge

Faraday F=eNI COMstanc

BoltzrTinn k cons3Ct

Gas costant n=kNA

PlancK constant h

h-h2T Avogadro Ni

constant

Atomic mass u unit

Mass of Iectron m proton m neutron m

Vacuum 1 permeabilityt

VaCtum r-lrrpopermittivity

tiro Bohr magneton ]I efl2m Nuclear

IN - en2mmagneton electron g

~value

Schr radius 2 4vm ( Rydber R ml4Shl c

constant

Fine nrucure C= Jloeh2hconstant

Gravitational G ccnSlant

tStandard gIIccelerinion ot free alit

f p n m

femto pico nano micro 10- 1S 10-111 10- 10-middot

Value General data and 2s97 9~42 x 10a m 5- 1 fundamental 160217T)lt) 0-111 C constantsmiddot

S64aS x 10 C mol-I

138066 X 10-1 J Kshy

83451 J 1(-1 mol-I

820578 x 10-2 cm1 atm 1(-1 mol-

62364 L TQrr 1(-1 mol

6526 as x 10---)1 J s

105457)c 10-)1 J oS 602214 x 1012 mol-I

1660 54 x 10-z kg

9109351 x 10-11 kg

167262 X 10-zr kg

middot167493 x Omiddotzr kg

4Jr Xmiddot 0-- J r C-2 m-r 4nx lomiddot7 T2J- ml

B8S4 19 X10-12J~1 C2 m-1

126Sx 1c-tG rIC2m-1

927402 x 10-10amp J T- SOSO 79 x 1o-zrJ I~

2C02~2

529~77 X 10-11 m

1091 37x 10cm-

7297 isx 10-3

65725S x la-II N m Zlcg-Z

bull aSOS 65Jil-~

r Exct Idilo Vllu

c d M G Prefixes deci kilo mega glgl

10-1 10 10middot 105

i) Draw the SHE and label all components What is the role for the platinum Why

is it a suitable metal for this role (3)

ii) What specifications should be met by the SHE (2)

iii) State the function of the salt bridge and explain how it works (2)

QUESTION 3

a) A young scientist determined the amount of Riboflavin (Vitamin B 2) in a cereal

sample by measuring its fluorescence intensity in 5 acetic acid solution A

calibration curve was prepared by measuring the fluorescence intensitiesrDf a series of

standards of increasing concentrations The concentration of the standard was found

to be 100 ppm Explain in detail TWO ways which the young scientists can use to show that the method and instrument used for measurements gives accurate results

(Give a detailed explanation how this would be achieved) (5)

b) An enzymatic method for determining alcohol in wine is evaluated by comparison

with gas-chromatographic (GC) method The sample is analysed several times by both

methods with the following results ( ethanol)

Enzymatic Method 131 127 126 133 133

GC Method 135 133 130 129

Does the enzymatic method give the same value as the GC method at the 95

confidence level (5)

c) One of the challenges in the quantification of elements is the problem of

interferences Explain what is meant by interferences giving a specific example and a

solution on how this interference can be eliminated in analytical chemistry (4)

d) A standard method for the determination of carbon monoxide (CO) level in gaseous

mixtures is known from many hundred measurements to have a standard deviation of

021 ppm CO A modification of the method yields a value for s ofO15ppm CO

pooled from data set with 12 degrees of freedom Does the modification give more

precise measurements than the original method (5)

3

e) An atomic absorption method for the determination of copper content in fuels yielded

a pooled standard deviation of spooled == 032 jlg CulmL (s ~ 0) The analysis ofthe

oil from a reciprocating aircraft engine showed a copper content of 853 Jg CulmL

i) Calculate the 99 confidence limits for the result based on a mean of four (4)

analyses (3)

ii) How many replicate measurements are necessary to decrease the 99

confidence for the analysis to plusmn 020 Jg CulmL (3)

QUESTION 4

a) The amount of iron (Fe) in drinking water was determined using the standard addition

method The concentration of the Fe standard was 111 ppm The dilutions and signals

for the different dilutions are given in the table below Calculate the amount of Fe in

the water sample in ppb

Sample Volume

(mL)

Standard Volume

(mL) Signal (V)

10 0 0215 10 5 0424 10 10 0685 10 15 0826 10 20 0967

Note All solutions were diluted to a fmal volume of 50 mL (7)

b) External calibration is one other method which can be used in the determination of

iron in water Explain in detail how external calibration differs from standard addition

and also give the main advantage of using standard addition over external calibration

(5)

4

c) Explain two disadvantages of using the standard addition method (3)

d) Internal calibration is another method ofcalibration which is used in determination of

the concentrations of unknown In detail explain the principle of internal standard

explain the advantage of using this type of method over the external calibration and

standard addition (7)

e) Give the three (3) properties which an internal standard should meet (3)

QUESTIONS

a) The CO in a 203 L sample of gas was converted to C02 by passing the gas over

iodine pentoxide heated to ISO degrees Celsius

hOs (s) + SCO (g) -4 SC02 (g) + h (g)

The iodine was distilled at this temperature and was collected in an absorber containing 82S

mL ofO01101 M Na2S203

h (g) + 2S20l- (aq) -4 2r (aq) + S40 (aq)

The excess Na2S203 was back titrated with 216 mL of 000947 M h solution

i) Calculate the concentration in milligrams of CO (2801 gmol) per litre of sample

(S)

ii) The method used in a(i) is known as back titration explain what is meant by back

titration (2)

iii) Give four (4) purposes of back titration ie cases which would require the use of

back titration instead ofdirect titration (4)

b) In titrimetry

i) Differentiate between primary standard and a secondary standard for

titrimetric analysis (2)

ii) Give four (4) desirable properties for a primary standard used for titration

purposes (4)

c) Titration Curves describe how pH changes during various acid-base titrations Draw

the titration curve for the titration of2S mL HCI of 0100 M with O1OOM HCl (S)

5

d) Using sketch diagrams explain what would be the difference ofa titration curve

obtained when 10 mL 01 M acetic acid is titrated with 01 M sodium hydroxide from

that of 01 M hydrochloric acid titrated with 01 M sodium hydroxide (Do not

Calculate) (3)

QUESTION 6

a) One of the properties of a homogeneous precipitate in gravimetry is that it has fewer

impurities Describe the (2) ways which can be used in the formation ofa

homogeneous precipitate Give an example for each (4)

b) Explain how the particle size of a precipitate can be controlled WIth reference to If

relative supersaturation (3)

c) i) What is meant by digestion ofa precipitate Briefly describe what happens in the

process of digesting a precipitate and give Q(2) advantages of this step during

gravimetric analysis (3)

ii) What is peptization Howcan this phenomenon be avoided during gravimetric

analysis (2)

d) One of the gravimetric titration methods used in analytical chemistry is the Volhard

titration

i) Describe the Volhard titration method What is this type of titration used for

(3)

ii) Give the two main challenges encountered when using this method of

titration (2)

iii) How can these problems listed in b(ii) be solved (2)

e) A 02356g sample containing only NaCI and BaCl2 Yielded 04637 g of dried Ag CI

on adding AgN03 to the sample Calculate the percent of each halogen compound in

the sample (6)

6

APPENDIX

bull VALUES OF tFOR VARIOUS LEVELS OF PROBABILITY

Number of Factor for Confidence Interval Observations

- 00~95 99~ 1 308 631 127 637

2 189 292 43 992 316

3_ 164 235 318 584 129

4shy -shy 153 213 278 46 86

5 148 202 257 403 686 ~

6 144 194 245 371 596

7 142 19 236 35 54

8 14 1 Qt I ~1 336 504

9 138 183 226 325 478

10 137 181 223 317 459

11 136 18 22 311 444

12 136 178 218 306 432

13 135 177 216 301 422

14 134 176 214 298 414

i CRITICAL VALUES FOR REJECITON QUOTIENT Q 1

Number of 1 90 95 ~I Icnnflrlpnr-p IIIObservations I Confidence Confidence I Confidence I

i 3 0941 0970 lit 09941 i shy

4 0765 0829t ~----__~rl________i________l~__0_9_2_6~r-5 1 0642 0710 0821 r_I

r----6-----rl---o-56-o---r--o-6-25---~1--0-7-4-0--r_

~----7----_~--0-50-7---r__0-5-68--~1--0-6-8-0--r-1 8 0468 0526 1 0634 r_l

~___9 ____li___0_~_7___lr__0_4_9_3_middot_rl__0_5_9_8__r_l

10 0412 0466 0568I I

Confidence Levels for Various Values middotofz

Confidence Level J z

-50

68 i

8amp

067

100

128

I

I I

shy

90

-

164

95 196

954 200

99 258

997 300

999 329

Degrees of Derees offreedom for 5J 1rledom

7 s III f

furl Z ) if 5 Ci ) 10 15 20 pO jQgt

1 190 192 l lQ2 193 193 1~41194 HU lQ4 liU 1M 194 195 195 3 9_~5 9211 i 912 WI 1194 iU9 IlP4 lUI 1179 874 Pi) RM I IUil 853 4 694 659 r 639 626 616 609 604 600 596 591 586 580 ~ 575 563 S 579 HI 519 505 495 4881 482 477 474 46-~ 462 456 i 450 436

6 Sl4 476 53 4J9 41S 421 4lS 41Q 406 400 394 181 1381 367

bull~ 414 435 412 gt97 387 379 373 368 164 353 351 ~A4 i 138 323 8 446 407 384 369 358 350 344 339 335 32S 122 31S i 308 293

9 426 186 )() 348 JJ7 129 323 3l8 314 3U7 lUl 294 I 286 271 Hl f-lt-4IO 371 l 343 333 3~ 314 301 Hi 293 291 284shy 271 2711 bull 254-__- _--_ _- I-shy --shy ---shy --_ - -~r-middot---middot middot __shyII 398 359 ~ 336 320 310 301 295 290 285 279 272 265 257 240- 2S4111 38 349 126 II 300 291 28S 280 275 260) 162 247 23(1

1 HI )41 i ItA Hi 1 92 Ul li7 lil -67 2M -~t -4Q 2 I~ 14 374 334 bull 311 296 21 276 270 16$ ltiO 251 246 239 [ 131 213 15 J()~ 3l~ 3Jl6 2Kl 271) 271 L2~ 159 254 24-~ 240 ali 225 ---shy -16 l6 324 1111 285 274 Vi( 2jil 250 249 242shy 2Ji 22R I 219 201 ]7 3J9 3W 296 281 270 261 255 249 245 23~ ln un Hi 196

219 t18 ~_6 SII) 293 11 2fi6 ]8 151 246 241 234 217 211 192 19 35 lnf 290 274 263 254shy l48 242 238 231 223 216 I201 188 20 349 lLO t 2$1 271 260 251 245 239 235 22~ 220 212 204 184 30 332 292 269 253 242 233 221 221 116 209 201 193 JS4 162 0 300 260 lJ7 221 lJO 201 194 1amp8 U3 J7~ 167 157 14( 100

USEFUL CONSTANTS

Ka Acid Base Name Formula Formula Name

Large Perchloric acid HCI04 CI04shy Perchlorate ion 32 10~ Hydroiodic acid HI 1shy Iodide 10 10~ Hydrobromic acid HBr Br- Bromide 13 lOb Hydrochloric acid HCI CI- Chloride 10 103 Sulfuric acid H2SO4 HS04shy Hydrogen sulfate ion 24 101

-Nitric acid RN03 N03shy Nitrate ion

-------shy Hydronium ion H3O+ H2O Water

~

Ka shy- - Acid Conjugate Base

Name Formula Formula Name Large -

Perchloric acid HCI04 CI04shy Perchlorate ion 32 10~ Hydroiodic acid HI 1shy Iodide 10 109 Hydrobromic acid HBr Br- Bromide 13 lOb Hydrochloric acid HCI CI- Chloride 10103 Sulfuric acid H2SO4 HS04shy Hydrogen sulfate ion 24 101 Nitric acid HN03 N03shy II Nitrate ion -------shy Hydronium ion H3O+ H2O Water

54 1O-l Oxalic acid H02C20 2H H02C20 2shy Hydrogen oxalate ion 13 1O-l Sulfurous acid H2S03 HS03shy Hydrogen sulfite ion 10 10-2 Hydrogen sulfate ion HS04shy S04 2- Sulfate ion 71 10-3 Phosphoric acid H3P04 H2P04- Dihydrogen phosphate

ion 72 10-4 Nitrous acid HN02 N03shy Nitrite ion 66 10-4 Hydrofluoric acid HF F- Fluoride ion 18 10-4 Methanoic acid HC02H HC02shy Methanoate ion 63 10- Benzoic acid C6HsCOOH C6HsCOOshy Benzoate ion 54 10- Hydrogen oxalate ion H02C20~- 02C20 2 ~- Oxalate ion 18 10- Ethanoic acid CH3COOH CH3COO Ethanoate (acetate)

ion 44 10- 1 Carbonic acid C03lshy HC03shy Hydrogen carbonate

ion 11 10-7 Hydrosulfuric acid H2S HS- Hydrogen sulfide ion 63 1O-~ Dihydrogen phosphate

ion H2P04shy HP04l- Hydrogen phosphate

ion 62 10-8 Hydrogen sulfite ion -lISshy S2shy Sulfite ion 29 10-~ Hypochlorous acid HCIO CIO- Hypochlorite ion 62 10-10 Hydrocyanic acid HCN CN- Cyanide ion 58 lO- IU Ammonium ion NH4 + NH3 Ammonia 58 10-10 Boric acid H3B03 H2Bq3 - Dihydrogen carbonate

ion 47 10-11 Hydrogen carbonate ion HC03shy C03 l- Carbonate ion 42 lO- lJ

Hydrogen phosphate ion

HP04lshy P04-shy Phosphate ion

18 10-13 Dihydrogen borate ion H2B03- HB03l- Hydrogen borate ion 13 10-1- Hydrogen sulfide ion HSshy S ~- Sulfide ion 16 10-14 Hydrogen borate ion HB03

2- B033shy Borate ion --------shy water H2O OH- Hydroxide

I

j 4

-f

I to

Ouantil Symbol r

Speed of lighr c Elemlfmary e

charge

Faraday F=eNI COMstanc

BoltzrTinn k cons3Ct

Gas costant n=kNA

PlancK constant h

h-h2T Avogadro Ni

constant

Atomic mass u unit

Mass of Iectron m proton m neutron m

Vacuum 1 permeabilityt

VaCtum r-lrrpopermittivity

tiro Bohr magneton ]I efl2m Nuclear

IN - en2mmagneton electron g

~value

Schr radius 2 4vm ( Rydber R ml4Shl c

constant

Fine nrucure C= Jloeh2hconstant

Gravitational G ccnSlant

tStandard gIIccelerinion ot free alit

f p n m

femto pico nano micro 10- 1S 10-111 10- 10-middot

Value General data and 2s97 9~42 x 10a m 5- 1 fundamental 160217T)lt) 0-111 C constantsmiddot

S64aS x 10 C mol-I

138066 X 10-1 J Kshy

83451 J 1(-1 mol-I

820578 x 10-2 cm1 atm 1(-1 mol-

62364 L TQrr 1(-1 mol

6526 as x 10---)1 J s

105457)c 10-)1 J oS 602214 x 1012 mol-I

1660 54 x 10-z kg

9109351 x 10-11 kg

167262 X 10-zr kg

middot167493 x Omiddotzr kg

4Jr Xmiddot 0-- J r C-2 m-r 4nx lomiddot7 T2J- ml

B8S4 19 X10-12J~1 C2 m-1

126Sx 1c-tG rIC2m-1

927402 x 10-10amp J T- SOSO 79 x 1o-zrJ I~

2C02~2

529~77 X 10-11 m

1091 37x 10cm-

7297 isx 10-3

65725S x la-II N m Zlcg-Z

bull aSOS 65Jil-~

r Exct Idilo Vllu

c d M G Prefixes deci kilo mega glgl

10-1 10 10middot 105

e) An atomic absorption method for the determination of copper content in fuels yielded

a pooled standard deviation of spooled == 032 jlg CulmL (s ~ 0) The analysis ofthe

oil from a reciprocating aircraft engine showed a copper content of 853 Jg CulmL

i) Calculate the 99 confidence limits for the result based on a mean of four (4)

analyses (3)

ii) How many replicate measurements are necessary to decrease the 99

confidence for the analysis to plusmn 020 Jg CulmL (3)

QUESTION 4

a) The amount of iron (Fe) in drinking water was determined using the standard addition

method The concentration of the Fe standard was 111 ppm The dilutions and signals

for the different dilutions are given in the table below Calculate the amount of Fe in

the water sample in ppb

Sample Volume

(mL)

Standard Volume

(mL) Signal (V)

10 0 0215 10 5 0424 10 10 0685 10 15 0826 10 20 0967

Note All solutions were diluted to a fmal volume of 50 mL (7)

b) External calibration is one other method which can be used in the determination of

iron in water Explain in detail how external calibration differs from standard addition

and also give the main advantage of using standard addition over external calibration

(5)

4

c) Explain two disadvantages of using the standard addition method (3)

d) Internal calibration is another method ofcalibration which is used in determination of

the concentrations of unknown In detail explain the principle of internal standard

explain the advantage of using this type of method over the external calibration and

standard addition (7)

e) Give the three (3) properties which an internal standard should meet (3)

QUESTIONS

a) The CO in a 203 L sample of gas was converted to C02 by passing the gas over

iodine pentoxide heated to ISO degrees Celsius

hOs (s) + SCO (g) -4 SC02 (g) + h (g)

The iodine was distilled at this temperature and was collected in an absorber containing 82S

mL ofO01101 M Na2S203

h (g) + 2S20l- (aq) -4 2r (aq) + S40 (aq)

The excess Na2S203 was back titrated with 216 mL of 000947 M h solution

i) Calculate the concentration in milligrams of CO (2801 gmol) per litre of sample

(S)

ii) The method used in a(i) is known as back titration explain what is meant by back

titration (2)

iii) Give four (4) purposes of back titration ie cases which would require the use of

back titration instead ofdirect titration (4)

b) In titrimetry

i) Differentiate between primary standard and a secondary standard for

titrimetric analysis (2)

ii) Give four (4) desirable properties for a primary standard used for titration

purposes (4)

c) Titration Curves describe how pH changes during various acid-base titrations Draw

the titration curve for the titration of2S mL HCI of 0100 M with O1OOM HCl (S)

5

d) Using sketch diagrams explain what would be the difference ofa titration curve

obtained when 10 mL 01 M acetic acid is titrated with 01 M sodium hydroxide from

that of 01 M hydrochloric acid titrated with 01 M sodium hydroxide (Do not

Calculate) (3)

QUESTION 6

a) One of the properties of a homogeneous precipitate in gravimetry is that it has fewer

impurities Describe the (2) ways which can be used in the formation ofa

homogeneous precipitate Give an example for each (4)

b) Explain how the particle size of a precipitate can be controlled WIth reference to If

relative supersaturation (3)

c) i) What is meant by digestion ofa precipitate Briefly describe what happens in the

process of digesting a precipitate and give Q(2) advantages of this step during

gravimetric analysis (3)

ii) What is peptization Howcan this phenomenon be avoided during gravimetric

analysis (2)

d) One of the gravimetric titration methods used in analytical chemistry is the Volhard

titration

i) Describe the Volhard titration method What is this type of titration used for

(3)

ii) Give the two main challenges encountered when using this method of

titration (2)

iii) How can these problems listed in b(ii) be solved (2)

e) A 02356g sample containing only NaCI and BaCl2 Yielded 04637 g of dried Ag CI

on adding AgN03 to the sample Calculate the percent of each halogen compound in

the sample (6)

6

APPENDIX

bull VALUES OF tFOR VARIOUS LEVELS OF PROBABILITY

Number of Factor for Confidence Interval Observations

- 00~95 99~ 1 308 631 127 637

2 189 292 43 992 316

3_ 164 235 318 584 129

4shy -shy 153 213 278 46 86

5 148 202 257 403 686 ~

6 144 194 245 371 596

7 142 19 236 35 54

8 14 1 Qt I ~1 336 504

9 138 183 226 325 478

10 137 181 223 317 459

11 136 18 22 311 444

12 136 178 218 306 432

13 135 177 216 301 422

14 134 176 214 298 414

i CRITICAL VALUES FOR REJECITON QUOTIENT Q 1

Number of 1 90 95 ~I Icnnflrlpnr-p IIIObservations I Confidence Confidence I Confidence I

i 3 0941 0970 lit 09941 i shy

4 0765 0829t ~----__~rl________i________l~__0_9_2_6~r-5 1 0642 0710 0821 r_I

r----6-----rl---o-56-o---r--o-6-25---~1--0-7-4-0--r_

~----7----_~--0-50-7---r__0-5-68--~1--0-6-8-0--r-1 8 0468 0526 1 0634 r_l

~___9 ____li___0_~_7___lr__0_4_9_3_middot_rl__0_5_9_8__r_l

10 0412 0466 0568I I

Confidence Levels for Various Values middotofz

Confidence Level J z

-50

68 i

8amp

067

100

128

I

I I

shy

90

-

164

95 196

954 200

99 258

997 300

999 329

Degrees of Derees offreedom for 5J 1rledom

7 s III f

furl Z ) if 5 Ci ) 10 15 20 pO jQgt

1 190 192 l lQ2 193 193 1~41194 HU lQ4 liU 1M 194 195 195 3 9_~5 9211 i 912 WI 1194 iU9 IlP4 lUI 1179 874 Pi) RM I IUil 853 4 694 659 r 639 626 616 609 604 600 596 591 586 580 ~ 575 563 S 579 HI 519 505 495 4881 482 477 474 46-~ 462 456 i 450 436

6 Sl4 476 53 4J9 41S 421 4lS 41Q 406 400 394 181 1381 367

bull~ 414 435 412 gt97 387 379 373 368 164 353 351 ~A4 i 138 323 8 446 407 384 369 358 350 344 339 335 32S 122 31S i 308 293

9 426 186 )() 348 JJ7 129 323 3l8 314 3U7 lUl 294 I 286 271 Hl f-lt-4IO 371 l 343 333 3~ 314 301 Hi 293 291 284shy 271 2711 bull 254-__- _--_ _- I-shy --shy ---shy --_ - -~r-middot---middot middot __shyII 398 359 ~ 336 320 310 301 295 290 285 279 272 265 257 240- 2S4111 38 349 126 II 300 291 28S 280 275 260) 162 247 23(1

1 HI )41 i ItA Hi 1 92 Ul li7 lil -67 2M -~t -4Q 2 I~ 14 374 334 bull 311 296 21 276 270 16$ ltiO 251 246 239 [ 131 213 15 J()~ 3l~ 3Jl6 2Kl 271) 271 L2~ 159 254 24-~ 240 ali 225 ---shy -16 l6 324 1111 285 274 Vi( 2jil 250 249 242shy 2Ji 22R I 219 201 ]7 3J9 3W 296 281 270 261 255 249 245 23~ ln un Hi 196

219 t18 ~_6 SII) 293 11 2fi6 ]8 151 246 241 234 217 211 192 19 35 lnf 290 274 263 254shy l48 242 238 231 223 216 I201 188 20 349 lLO t 2$1 271 260 251 245 239 235 22~ 220 212 204 184 30 332 292 269 253 242 233 221 221 116 209 201 193 JS4 162 0 300 260 lJ7 221 lJO 201 194 1amp8 U3 J7~ 167 157 14( 100

USEFUL CONSTANTS

Ka Acid Base Name Formula Formula Name

Large Perchloric acid HCI04 CI04shy Perchlorate ion 32 10~ Hydroiodic acid HI 1shy Iodide 10 10~ Hydrobromic acid HBr Br- Bromide 13 lOb Hydrochloric acid HCI CI- Chloride 10 103 Sulfuric acid H2SO4 HS04shy Hydrogen sulfate ion 24 101

-Nitric acid RN03 N03shy Nitrate ion

-------shy Hydronium ion H3O+ H2O Water

~

Ka shy- - Acid Conjugate Base

Name Formula Formula Name Large -

Perchloric acid HCI04 CI04shy Perchlorate ion 32 10~ Hydroiodic acid HI 1shy Iodide 10 109 Hydrobromic acid HBr Br- Bromide 13 lOb Hydrochloric acid HCI CI- Chloride 10103 Sulfuric acid H2SO4 HS04shy Hydrogen sulfate ion 24 101 Nitric acid HN03 N03shy II Nitrate ion -------shy Hydronium ion H3O+ H2O Water

54 1O-l Oxalic acid H02C20 2H H02C20 2shy Hydrogen oxalate ion 13 1O-l Sulfurous acid H2S03 HS03shy Hydrogen sulfite ion 10 10-2 Hydrogen sulfate ion HS04shy S04 2- Sulfate ion 71 10-3 Phosphoric acid H3P04 H2P04- Dihydrogen phosphate

ion 72 10-4 Nitrous acid HN02 N03shy Nitrite ion 66 10-4 Hydrofluoric acid HF F- Fluoride ion 18 10-4 Methanoic acid HC02H HC02shy Methanoate ion 63 10- Benzoic acid C6HsCOOH C6HsCOOshy Benzoate ion 54 10- Hydrogen oxalate ion H02C20~- 02C20 2 ~- Oxalate ion 18 10- Ethanoic acid CH3COOH CH3COO Ethanoate (acetate)

ion 44 10- 1 Carbonic acid C03lshy HC03shy Hydrogen carbonate

ion 11 10-7 Hydrosulfuric acid H2S HS- Hydrogen sulfide ion 63 1O-~ Dihydrogen phosphate

ion H2P04shy HP04l- Hydrogen phosphate

ion 62 10-8 Hydrogen sulfite ion -lISshy S2shy Sulfite ion 29 10-~ Hypochlorous acid HCIO CIO- Hypochlorite ion 62 10-10 Hydrocyanic acid HCN CN- Cyanide ion 58 lO- IU Ammonium ion NH4 + NH3 Ammonia 58 10-10 Boric acid H3B03 H2Bq3 - Dihydrogen carbonate

ion 47 10-11 Hydrogen carbonate ion HC03shy C03 l- Carbonate ion 42 lO- lJ

Hydrogen phosphate ion

HP04lshy P04-shy Phosphate ion

18 10-13 Dihydrogen borate ion H2B03- HB03l- Hydrogen borate ion 13 10-1- Hydrogen sulfide ion HSshy S ~- Sulfide ion 16 10-14 Hydrogen borate ion HB03

2- B033shy Borate ion --------shy water H2O OH- Hydroxide

I

j 4

-f

I to

Ouantil Symbol r

Speed of lighr c Elemlfmary e

charge

Faraday F=eNI COMstanc

BoltzrTinn k cons3Ct

Gas costant n=kNA

PlancK constant h

h-h2T Avogadro Ni

constant

Atomic mass u unit

Mass of Iectron m proton m neutron m

Vacuum 1 permeabilityt

VaCtum r-lrrpopermittivity

tiro Bohr magneton ]I efl2m Nuclear

IN - en2mmagneton electron g

~value

Schr radius 2 4vm ( Rydber R ml4Shl c

constant

Fine nrucure C= Jloeh2hconstant

Gravitational G ccnSlant

tStandard gIIccelerinion ot free alit

f p n m

femto pico nano micro 10- 1S 10-111 10- 10-middot

Value General data and 2s97 9~42 x 10a m 5- 1 fundamental 160217T)lt) 0-111 C constantsmiddot

S64aS x 10 C mol-I

138066 X 10-1 J Kshy

83451 J 1(-1 mol-I

820578 x 10-2 cm1 atm 1(-1 mol-

62364 L TQrr 1(-1 mol

6526 as x 10---)1 J s

105457)c 10-)1 J oS 602214 x 1012 mol-I

1660 54 x 10-z kg

9109351 x 10-11 kg

167262 X 10-zr kg

middot167493 x Omiddotzr kg

4Jr Xmiddot 0-- J r C-2 m-r 4nx lomiddot7 T2J- ml

B8S4 19 X10-12J~1 C2 m-1

126Sx 1c-tG rIC2m-1

927402 x 10-10amp J T- SOSO 79 x 1o-zrJ I~

2C02~2

529~77 X 10-11 m

1091 37x 10cm-

7297 isx 10-3

65725S x la-II N m Zlcg-Z

bull aSOS 65Jil-~

r Exct Idilo Vllu

c d M G Prefixes deci kilo mega glgl

10-1 10 10middot 105

c) Explain two disadvantages of using the standard addition method (3)

d) Internal calibration is another method ofcalibration which is used in determination of

the concentrations of unknown In detail explain the principle of internal standard

explain the advantage of using this type of method over the external calibration and

standard addition (7)

e) Give the three (3) properties which an internal standard should meet (3)

QUESTIONS

a) The CO in a 203 L sample of gas was converted to C02 by passing the gas over

iodine pentoxide heated to ISO degrees Celsius

hOs (s) + SCO (g) -4 SC02 (g) + h (g)

The iodine was distilled at this temperature and was collected in an absorber containing 82S

mL ofO01101 M Na2S203

h (g) + 2S20l- (aq) -4 2r (aq) + S40 (aq)

The excess Na2S203 was back titrated with 216 mL of 000947 M h solution

i) Calculate the concentration in milligrams of CO (2801 gmol) per litre of sample

(S)

ii) The method used in a(i) is known as back titration explain what is meant by back

titration (2)

iii) Give four (4) purposes of back titration ie cases which would require the use of

back titration instead ofdirect titration (4)

b) In titrimetry

i) Differentiate between primary standard and a secondary standard for

titrimetric analysis (2)

ii) Give four (4) desirable properties for a primary standard used for titration

purposes (4)

c) Titration Curves describe how pH changes during various acid-base titrations Draw

the titration curve for the titration of2S mL HCI of 0100 M with O1OOM HCl (S)

5

d) Using sketch diagrams explain what would be the difference ofa titration curve

obtained when 10 mL 01 M acetic acid is titrated with 01 M sodium hydroxide from

that of 01 M hydrochloric acid titrated with 01 M sodium hydroxide (Do not

Calculate) (3)

QUESTION 6

a) One of the properties of a homogeneous precipitate in gravimetry is that it has fewer

impurities Describe the (2) ways which can be used in the formation ofa

homogeneous precipitate Give an example for each (4)

b) Explain how the particle size of a precipitate can be controlled WIth reference to If

relative supersaturation (3)

c) i) What is meant by digestion ofa precipitate Briefly describe what happens in the

process of digesting a precipitate and give Q(2) advantages of this step during

gravimetric analysis (3)

ii) What is peptization Howcan this phenomenon be avoided during gravimetric

analysis (2)

d) One of the gravimetric titration methods used in analytical chemistry is the Volhard

titration

i) Describe the Volhard titration method What is this type of titration used for

(3)

ii) Give the two main challenges encountered when using this method of

titration (2)

iii) How can these problems listed in b(ii) be solved (2)

e) A 02356g sample containing only NaCI and BaCl2 Yielded 04637 g of dried Ag CI

on adding AgN03 to the sample Calculate the percent of each halogen compound in

the sample (6)

6

APPENDIX

bull VALUES OF tFOR VARIOUS LEVELS OF PROBABILITY

Number of Factor for Confidence Interval Observations

- 00~95 99~ 1 308 631 127 637

2 189 292 43 992 316

3_ 164 235 318 584 129

4shy -shy 153 213 278 46 86

5 148 202 257 403 686 ~

6 144 194 245 371 596

7 142 19 236 35 54

8 14 1 Qt I ~1 336 504

9 138 183 226 325 478

10 137 181 223 317 459

11 136 18 22 311 444

12 136 178 218 306 432

13 135 177 216 301 422

14 134 176 214 298 414

i CRITICAL VALUES FOR REJECITON QUOTIENT Q 1

Number of 1 90 95 ~I Icnnflrlpnr-p IIIObservations I Confidence Confidence I Confidence I

i 3 0941 0970 lit 09941 i shy

4 0765 0829t ~----__~rl________i________l~__0_9_2_6~r-5 1 0642 0710 0821 r_I

r----6-----rl---o-56-o---r--o-6-25---~1--0-7-4-0--r_

~----7----_~--0-50-7---r__0-5-68--~1--0-6-8-0--r-1 8 0468 0526 1 0634 r_l

~___9 ____li___0_~_7___lr__0_4_9_3_middot_rl__0_5_9_8__r_l

10 0412 0466 0568I I

Confidence Levels for Various Values middotofz

Confidence Level J z

-50

68 i

8amp

067

100

128

I

I I

shy

90

-

164

95 196

954 200

99 258

997 300

999 329

Degrees of Derees offreedom for 5J 1rledom

7 s III f

furl Z ) if 5 Ci ) 10 15 20 pO jQgt

1 190 192 l lQ2 193 193 1~41194 HU lQ4 liU 1M 194 195 195 3 9_~5 9211 i 912 WI 1194 iU9 IlP4 lUI 1179 874 Pi) RM I IUil 853 4 694 659 r 639 626 616 609 604 600 596 591 586 580 ~ 575 563 S 579 HI 519 505 495 4881 482 477 474 46-~ 462 456 i 450 436

6 Sl4 476 53 4J9 41S 421 4lS 41Q 406 400 394 181 1381 367

bull~ 414 435 412 gt97 387 379 373 368 164 353 351 ~A4 i 138 323 8 446 407 384 369 358 350 344 339 335 32S 122 31S i 308 293

9 426 186 )() 348 JJ7 129 323 3l8 314 3U7 lUl 294 I 286 271 Hl f-lt-4IO 371 l 343 333 3~ 314 301 Hi 293 291 284shy 271 2711 bull 254-__- _--_ _- I-shy --shy ---shy --_ - -~r-middot---middot middot __shyII 398 359 ~ 336 320 310 301 295 290 285 279 272 265 257 240- 2S4111 38 349 126 II 300 291 28S 280 275 260) 162 247 23(1

1 HI )41 i ItA Hi 1 92 Ul li7 lil -67 2M -~t -4Q 2 I~ 14 374 334 bull 311 296 21 276 270 16$ ltiO 251 246 239 [ 131 213 15 J()~ 3l~ 3Jl6 2Kl 271) 271 L2~ 159 254 24-~ 240 ali 225 ---shy -16 l6 324 1111 285 274 Vi( 2jil 250 249 242shy 2Ji 22R I 219 201 ]7 3J9 3W 296 281 270 261 255 249 245 23~ ln un Hi 196

219 t18 ~_6 SII) 293 11 2fi6 ]8 151 246 241 234 217 211 192 19 35 lnf 290 274 263 254shy l48 242 238 231 223 216 I201 188 20 349 lLO t 2$1 271 260 251 245 239 235 22~ 220 212 204 184 30 332 292 269 253 242 233 221 221 116 209 201 193 JS4 162 0 300 260 lJ7 221 lJO 201 194 1amp8 U3 J7~ 167 157 14( 100

USEFUL CONSTANTS

Ka Acid Base Name Formula Formula Name

Large Perchloric acid HCI04 CI04shy Perchlorate ion 32 10~ Hydroiodic acid HI 1shy Iodide 10 10~ Hydrobromic acid HBr Br- Bromide 13 lOb Hydrochloric acid HCI CI- Chloride 10 103 Sulfuric acid H2SO4 HS04shy Hydrogen sulfate ion 24 101

-Nitric acid RN03 N03shy Nitrate ion

-------shy Hydronium ion H3O+ H2O Water

~

Ka shy- - Acid Conjugate Base

Name Formula Formula Name Large -

Perchloric acid HCI04 CI04shy Perchlorate ion 32 10~ Hydroiodic acid HI 1shy Iodide 10 109 Hydrobromic acid HBr Br- Bromide 13 lOb Hydrochloric acid HCI CI- Chloride 10103 Sulfuric acid H2SO4 HS04shy Hydrogen sulfate ion 24 101 Nitric acid HN03 N03shy II Nitrate ion -------shy Hydronium ion H3O+ H2O Water

54 1O-l Oxalic acid H02C20 2H H02C20 2shy Hydrogen oxalate ion 13 1O-l Sulfurous acid H2S03 HS03shy Hydrogen sulfite ion 10 10-2 Hydrogen sulfate ion HS04shy S04 2- Sulfate ion 71 10-3 Phosphoric acid H3P04 H2P04- Dihydrogen phosphate

ion 72 10-4 Nitrous acid HN02 N03shy Nitrite ion 66 10-4 Hydrofluoric acid HF F- Fluoride ion 18 10-4 Methanoic acid HC02H HC02shy Methanoate ion 63 10- Benzoic acid C6HsCOOH C6HsCOOshy Benzoate ion 54 10- Hydrogen oxalate ion H02C20~- 02C20 2 ~- Oxalate ion 18 10- Ethanoic acid CH3COOH CH3COO Ethanoate (acetate)

ion 44 10- 1 Carbonic acid C03lshy HC03shy Hydrogen carbonate

ion 11 10-7 Hydrosulfuric acid H2S HS- Hydrogen sulfide ion 63 1O-~ Dihydrogen phosphate

ion H2P04shy HP04l- Hydrogen phosphate

ion 62 10-8 Hydrogen sulfite ion -lISshy S2shy Sulfite ion 29 10-~ Hypochlorous acid HCIO CIO- Hypochlorite ion 62 10-10 Hydrocyanic acid HCN CN- Cyanide ion 58 lO- IU Ammonium ion NH4 + NH3 Ammonia 58 10-10 Boric acid H3B03 H2Bq3 - Dihydrogen carbonate

ion 47 10-11 Hydrogen carbonate ion HC03shy C03 l- Carbonate ion 42 lO- lJ

Hydrogen phosphate ion

HP04lshy P04-shy Phosphate ion

18 10-13 Dihydrogen borate ion H2B03- HB03l- Hydrogen borate ion 13 10-1- Hydrogen sulfide ion HSshy S ~- Sulfide ion 16 10-14 Hydrogen borate ion HB03

2- B033shy Borate ion --------shy water H2O OH- Hydroxide

I

j 4

-f

I to

Ouantil Symbol r

Speed of lighr c Elemlfmary e

charge

Faraday F=eNI COMstanc

BoltzrTinn k cons3Ct

Gas costant n=kNA

PlancK constant h

h-h2T Avogadro Ni

constant

Atomic mass u unit

Mass of Iectron m proton m neutron m

Vacuum 1 permeabilityt

VaCtum r-lrrpopermittivity

tiro Bohr magneton ]I efl2m Nuclear

IN - en2mmagneton electron g

~value

Schr radius 2 4vm ( Rydber R ml4Shl c

constant

Fine nrucure C= Jloeh2hconstant

Gravitational G ccnSlant

tStandard gIIccelerinion ot free alit

f p n m

femto pico nano micro 10- 1S 10-111 10- 10-middot

Value General data and 2s97 9~42 x 10a m 5- 1 fundamental 160217T)lt) 0-111 C constantsmiddot

S64aS x 10 C mol-I

138066 X 10-1 J Kshy

83451 J 1(-1 mol-I

820578 x 10-2 cm1 atm 1(-1 mol-

62364 L TQrr 1(-1 mol

6526 as x 10---)1 J s

105457)c 10-)1 J oS 602214 x 1012 mol-I

1660 54 x 10-z kg

9109351 x 10-11 kg

167262 X 10-zr kg

middot167493 x Omiddotzr kg

4Jr Xmiddot 0-- J r C-2 m-r 4nx lomiddot7 T2J- ml

B8S4 19 X10-12J~1 C2 m-1

126Sx 1c-tG rIC2m-1

927402 x 10-10amp J T- SOSO 79 x 1o-zrJ I~

2C02~2

529~77 X 10-11 m

1091 37x 10cm-

7297 isx 10-3

65725S x la-II N m Zlcg-Z

bull aSOS 65Jil-~

r Exct Idilo Vllu

c d M G Prefixes deci kilo mega glgl

10-1 10 10middot 105

d) Using sketch diagrams explain what would be the difference ofa titration curve

obtained when 10 mL 01 M acetic acid is titrated with 01 M sodium hydroxide from

that of 01 M hydrochloric acid titrated with 01 M sodium hydroxide (Do not

Calculate) (3)

QUESTION 6

a) One of the properties of a homogeneous precipitate in gravimetry is that it has fewer

impurities Describe the (2) ways which can be used in the formation ofa

homogeneous precipitate Give an example for each (4)

b) Explain how the particle size of a precipitate can be controlled WIth reference to If

relative supersaturation (3)

c) i) What is meant by digestion ofa precipitate Briefly describe what happens in the

process of digesting a precipitate and give Q(2) advantages of this step during

gravimetric analysis (3)

ii) What is peptization Howcan this phenomenon be avoided during gravimetric

analysis (2)

d) One of the gravimetric titration methods used in analytical chemistry is the Volhard

titration

i) Describe the Volhard titration method What is this type of titration used for

(3)

ii) Give the two main challenges encountered when using this method of

titration (2)

iii) How can these problems listed in b(ii) be solved (2)

e) A 02356g sample containing only NaCI and BaCl2 Yielded 04637 g of dried Ag CI

on adding AgN03 to the sample Calculate the percent of each halogen compound in

the sample (6)

6

APPENDIX

bull VALUES OF tFOR VARIOUS LEVELS OF PROBABILITY

Number of Factor for Confidence Interval Observations

- 00~95 99~ 1 308 631 127 637

2 189 292 43 992 316

3_ 164 235 318 584 129

4shy -shy 153 213 278 46 86

5 148 202 257 403 686 ~

6 144 194 245 371 596

7 142 19 236 35 54

8 14 1 Qt I ~1 336 504

9 138 183 226 325 478

10 137 181 223 317 459

11 136 18 22 311 444

12 136 178 218 306 432

13 135 177 216 301 422

14 134 176 214 298 414

i CRITICAL VALUES FOR REJECITON QUOTIENT Q 1

Number of 1 90 95 ~I Icnnflrlpnr-p IIIObservations I Confidence Confidence I Confidence I

i 3 0941 0970 lit 09941 i shy

4 0765 0829t ~----__~rl________i________l~__0_9_2_6~r-5 1 0642 0710 0821 r_I

r----6-----rl---o-56-o---r--o-6-25---~1--0-7-4-0--r_

~----7----_~--0-50-7---r__0-5-68--~1--0-6-8-0--r-1 8 0468 0526 1 0634 r_l

~___9 ____li___0_~_7___lr__0_4_9_3_middot_rl__0_5_9_8__r_l

10 0412 0466 0568I I

Confidence Levels for Various Values middotofz

Confidence Level J z

-50

68 i

8amp

067

100

128

I

I I

shy

90

-

164

95 196

954 200

99 258

997 300

999 329

Degrees of Derees offreedom for 5J 1rledom

7 s III f

furl Z ) if 5 Ci ) 10 15 20 pO jQgt

1 190 192 l lQ2 193 193 1~41194 HU lQ4 liU 1M 194 195 195 3 9_~5 9211 i 912 WI 1194 iU9 IlP4 lUI 1179 874 Pi) RM I IUil 853 4 694 659 r 639 626 616 609 604 600 596 591 586 580 ~ 575 563 S 579 HI 519 505 495 4881 482 477 474 46-~ 462 456 i 450 436

6 Sl4 476 53 4J9 41S 421 4lS 41Q 406 400 394 181 1381 367

bull~ 414 435 412 gt97 387 379 373 368 164 353 351 ~A4 i 138 323 8 446 407 384 369 358 350 344 339 335 32S 122 31S i 308 293

9 426 186 )() 348 JJ7 129 323 3l8 314 3U7 lUl 294 I 286 271 Hl f-lt-4IO 371 l 343 333 3~ 314 301 Hi 293 291 284shy 271 2711 bull 254-__- _--_ _- I-shy --shy ---shy --_ - -~r-middot---middot middot __shyII 398 359 ~ 336 320 310 301 295 290 285 279 272 265 257 240- 2S4111 38 349 126 II 300 291 28S 280 275 260) 162 247 23(1

1 HI )41 i ItA Hi 1 92 Ul li7 lil -67 2M -~t -4Q 2 I~ 14 374 334 bull 311 296 21 276 270 16$ ltiO 251 246 239 [ 131 213 15 J()~ 3l~ 3Jl6 2Kl 271) 271 L2~ 159 254 24-~ 240 ali 225 ---shy -16 l6 324 1111 285 274 Vi( 2jil 250 249 242shy 2Ji 22R I 219 201 ]7 3J9 3W 296 281 270 261 255 249 245 23~ ln un Hi 196

219 t18 ~_6 SII) 293 11 2fi6 ]8 151 246 241 234 217 211 192 19 35 lnf 290 274 263 254shy l48 242 238 231 223 216 I201 188 20 349 lLO t 2$1 271 260 251 245 239 235 22~ 220 212 204 184 30 332 292 269 253 242 233 221 221 116 209 201 193 JS4 162 0 300 260 lJ7 221 lJO 201 194 1amp8 U3 J7~ 167 157 14( 100

USEFUL CONSTANTS

Ka Acid Base Name Formula Formula Name

Large Perchloric acid HCI04 CI04shy Perchlorate ion 32 10~ Hydroiodic acid HI 1shy Iodide 10 10~ Hydrobromic acid HBr Br- Bromide 13 lOb Hydrochloric acid HCI CI- Chloride 10 103 Sulfuric acid H2SO4 HS04shy Hydrogen sulfate ion 24 101

-Nitric acid RN03 N03shy Nitrate ion

-------shy Hydronium ion H3O+ H2O Water

~

Ka shy- - Acid Conjugate Base

Name Formula Formula Name Large -

Perchloric acid HCI04 CI04shy Perchlorate ion 32 10~ Hydroiodic acid HI 1shy Iodide 10 109 Hydrobromic acid HBr Br- Bromide 13 lOb Hydrochloric acid HCI CI- Chloride 10103 Sulfuric acid H2SO4 HS04shy Hydrogen sulfate ion 24 101 Nitric acid HN03 N03shy II Nitrate ion -------shy Hydronium ion H3O+ H2O Water

54 1O-l Oxalic acid H02C20 2H H02C20 2shy Hydrogen oxalate ion 13 1O-l Sulfurous acid H2S03 HS03shy Hydrogen sulfite ion 10 10-2 Hydrogen sulfate ion HS04shy S04 2- Sulfate ion 71 10-3 Phosphoric acid H3P04 H2P04- Dihydrogen phosphate

ion 72 10-4 Nitrous acid HN02 N03shy Nitrite ion 66 10-4 Hydrofluoric acid HF F- Fluoride ion 18 10-4 Methanoic acid HC02H HC02shy Methanoate ion 63 10- Benzoic acid C6HsCOOH C6HsCOOshy Benzoate ion 54 10- Hydrogen oxalate ion H02C20~- 02C20 2 ~- Oxalate ion 18 10- Ethanoic acid CH3COOH CH3COO Ethanoate (acetate)

ion 44 10- 1 Carbonic acid C03lshy HC03shy Hydrogen carbonate

ion 11 10-7 Hydrosulfuric acid H2S HS- Hydrogen sulfide ion 63 1O-~ Dihydrogen phosphate

ion H2P04shy HP04l- Hydrogen phosphate

ion 62 10-8 Hydrogen sulfite ion -lISshy S2shy Sulfite ion 29 10-~ Hypochlorous acid HCIO CIO- Hypochlorite ion 62 10-10 Hydrocyanic acid HCN CN- Cyanide ion 58 lO- IU Ammonium ion NH4 + NH3 Ammonia 58 10-10 Boric acid H3B03 H2Bq3 - Dihydrogen carbonate

ion 47 10-11 Hydrogen carbonate ion HC03shy C03 l- Carbonate ion 42 lO- lJ

Hydrogen phosphate ion

HP04lshy P04-shy Phosphate ion

18 10-13 Dihydrogen borate ion H2B03- HB03l- Hydrogen borate ion 13 10-1- Hydrogen sulfide ion HSshy S ~- Sulfide ion 16 10-14 Hydrogen borate ion HB03

2- B033shy Borate ion --------shy water H2O OH- Hydroxide

I

j 4

-f

I to

Ouantil Symbol r

Speed of lighr c Elemlfmary e

charge

Faraday F=eNI COMstanc

BoltzrTinn k cons3Ct

Gas costant n=kNA

PlancK constant h

h-h2T Avogadro Ni

constant

Atomic mass u unit

Mass of Iectron m proton m neutron m

Vacuum 1 permeabilityt

VaCtum r-lrrpopermittivity

tiro Bohr magneton ]I efl2m Nuclear

IN - en2mmagneton electron g

~value

Schr radius 2 4vm ( Rydber R ml4Shl c

constant

Fine nrucure C= Jloeh2hconstant

Gravitational G ccnSlant

tStandard gIIccelerinion ot free alit

f p n m

femto pico nano micro 10- 1S 10-111 10- 10-middot

Value General data and 2s97 9~42 x 10a m 5- 1 fundamental 160217T)lt) 0-111 C constantsmiddot

S64aS x 10 C mol-I

138066 X 10-1 J Kshy

83451 J 1(-1 mol-I

820578 x 10-2 cm1 atm 1(-1 mol-

62364 L TQrr 1(-1 mol

6526 as x 10---)1 J s

105457)c 10-)1 J oS 602214 x 1012 mol-I

1660 54 x 10-z kg

9109351 x 10-11 kg

167262 X 10-zr kg

middot167493 x Omiddotzr kg

4Jr Xmiddot 0-- J r C-2 m-r 4nx lomiddot7 T2J- ml

B8S4 19 X10-12J~1 C2 m-1

126Sx 1c-tG rIC2m-1

927402 x 10-10amp J T- SOSO 79 x 1o-zrJ I~

2C02~2

529~77 X 10-11 m

1091 37x 10cm-

7297 isx 10-3

65725S x la-II N m Zlcg-Z

bull aSOS 65Jil-~

r Exct Idilo Vllu

c d M G Prefixes deci kilo mega glgl

10-1 10 10middot 105

APPENDIX

bull VALUES OF tFOR VARIOUS LEVELS OF PROBABILITY

Number of Factor for Confidence Interval Observations

- 00~95 99~ 1 308 631 127 637

2 189 292 43 992 316

3_ 164 235 318 584 129

4shy -shy 153 213 278 46 86

5 148 202 257 403 686 ~

6 144 194 245 371 596

7 142 19 236 35 54

8 14 1 Qt I ~1 336 504

9 138 183 226 325 478

10 137 181 223 317 459

11 136 18 22 311 444

12 136 178 218 306 432

13 135 177 216 301 422

14 134 176 214 298 414

i CRITICAL VALUES FOR REJECITON QUOTIENT Q 1

Number of 1 90 95 ~I Icnnflrlpnr-p IIIObservations I Confidence Confidence I Confidence I

i 3 0941 0970 lit 09941 i shy

4 0765 0829t ~----__~rl________i________l~__0_9_2_6~r-5 1 0642 0710 0821 r_I

r----6-----rl---o-56-o---r--o-6-25---~1--0-7-4-0--r_

~----7----_~--0-50-7---r__0-5-68--~1--0-6-8-0--r-1 8 0468 0526 1 0634 r_l

~___9 ____li___0_~_7___lr__0_4_9_3_middot_rl__0_5_9_8__r_l

10 0412 0466 0568I I

Confidence Levels for Various Values middotofz

Confidence Level J z

-50

68 i

8amp

067

100

128

I

I I

shy

90

-

164

95 196

954 200

99 258

997 300

999 329

Degrees of Derees offreedom for 5J 1rledom

7 s III f

furl Z ) if 5 Ci ) 10 15 20 pO jQgt

1 190 192 l lQ2 193 193 1~41194 HU lQ4 liU 1M 194 195 195 3 9_~5 9211 i 912 WI 1194 iU9 IlP4 lUI 1179 874 Pi) RM I IUil 853 4 694 659 r 639 626 616 609 604 600 596 591 586 580 ~ 575 563 S 579 HI 519 505 495 4881 482 477 474 46-~ 462 456 i 450 436

6 Sl4 476 53 4J9 41S 421 4lS 41Q 406 400 394 181 1381 367

bull~ 414 435 412 gt97 387 379 373 368 164 353 351 ~A4 i 138 323 8 446 407 384 369 358 350 344 339 335 32S 122 31S i 308 293

9 426 186 )() 348 JJ7 129 323 3l8 314 3U7 lUl 294 I 286 271 Hl f-lt-4IO 371 l 343 333 3~ 314 301 Hi 293 291 284shy 271 2711 bull 254-__- _--_ _- I-shy --shy ---shy --_ - -~r-middot---middot middot __shyII 398 359 ~ 336 320 310 301 295 290 285 279 272 265 257 240- 2S4111 38 349 126 II 300 291 28S 280 275 260) 162 247 23(1

1 HI )41 i ItA Hi 1 92 Ul li7 lil -67 2M -~t -4Q 2 I~ 14 374 334 bull 311 296 21 276 270 16$ ltiO 251 246 239 [ 131 213 15 J()~ 3l~ 3Jl6 2Kl 271) 271 L2~ 159 254 24-~ 240 ali 225 ---shy -16 l6 324 1111 285 274 Vi( 2jil 250 249 242shy 2Ji 22R I 219 201 ]7 3J9 3W 296 281 270 261 255 249 245 23~ ln un Hi 196

219 t18 ~_6 SII) 293 11 2fi6 ]8 151 246 241 234 217 211 192 19 35 lnf 290 274 263 254shy l48 242 238 231 223 216 I201 188 20 349 lLO t 2$1 271 260 251 245 239 235 22~ 220 212 204 184 30 332 292 269 253 242 233 221 221 116 209 201 193 JS4 162 0 300 260 lJ7 221 lJO 201 194 1amp8 U3 J7~ 167 157 14( 100

USEFUL CONSTANTS

Ka Acid Base Name Formula Formula Name

Large Perchloric acid HCI04 CI04shy Perchlorate ion 32 10~ Hydroiodic acid HI 1shy Iodide 10 10~ Hydrobromic acid HBr Br- Bromide 13 lOb Hydrochloric acid HCI CI- Chloride 10 103 Sulfuric acid H2SO4 HS04shy Hydrogen sulfate ion 24 101

-Nitric acid RN03 N03shy Nitrate ion

-------shy Hydronium ion H3O+ H2O Water

~

Ka shy- - Acid Conjugate Base

Name Formula Formula Name Large -

Perchloric acid HCI04 CI04shy Perchlorate ion 32 10~ Hydroiodic acid HI 1shy Iodide 10 109 Hydrobromic acid HBr Br- Bromide 13 lOb Hydrochloric acid HCI CI- Chloride 10103 Sulfuric acid H2SO4 HS04shy Hydrogen sulfate ion 24 101 Nitric acid HN03 N03shy II Nitrate ion -------shy Hydronium ion H3O+ H2O Water

54 1O-l Oxalic acid H02C20 2H H02C20 2shy Hydrogen oxalate ion 13 1O-l Sulfurous acid H2S03 HS03shy Hydrogen sulfite ion 10 10-2 Hydrogen sulfate ion HS04shy S04 2- Sulfate ion 71 10-3 Phosphoric acid H3P04 H2P04- Dihydrogen phosphate

ion 72 10-4 Nitrous acid HN02 N03shy Nitrite ion 66 10-4 Hydrofluoric acid HF F- Fluoride ion 18 10-4 Methanoic acid HC02H HC02shy Methanoate ion 63 10- Benzoic acid C6HsCOOH C6HsCOOshy Benzoate ion 54 10- Hydrogen oxalate ion H02C20~- 02C20 2 ~- Oxalate ion 18 10- Ethanoic acid CH3COOH CH3COO Ethanoate (acetate)

ion 44 10- 1 Carbonic acid C03lshy HC03shy Hydrogen carbonate

ion 11 10-7 Hydrosulfuric acid H2S HS- Hydrogen sulfide ion 63 1O-~ Dihydrogen phosphate

ion H2P04shy HP04l- Hydrogen phosphate

ion 62 10-8 Hydrogen sulfite ion -lISshy S2shy Sulfite ion 29 10-~ Hypochlorous acid HCIO CIO- Hypochlorite ion 62 10-10 Hydrocyanic acid HCN CN- Cyanide ion 58 lO- IU Ammonium ion NH4 + NH3 Ammonia 58 10-10 Boric acid H3B03 H2Bq3 - Dihydrogen carbonate

ion 47 10-11 Hydrogen carbonate ion HC03shy C03 l- Carbonate ion 42 lO- lJ

Hydrogen phosphate ion

HP04lshy P04-shy Phosphate ion

18 10-13 Dihydrogen borate ion H2B03- HB03l- Hydrogen borate ion 13 10-1- Hydrogen sulfide ion HSshy S ~- Sulfide ion 16 10-14 Hydrogen borate ion HB03

2- B033shy Borate ion --------shy water H2O OH- Hydroxide

I

j 4

-f

I to

Ouantil Symbol r

Speed of lighr c Elemlfmary e

charge

Faraday F=eNI COMstanc

BoltzrTinn k cons3Ct

Gas costant n=kNA

PlancK constant h

h-h2T Avogadro Ni

constant

Atomic mass u unit

Mass of Iectron m proton m neutron m

Vacuum 1 permeabilityt

VaCtum r-lrrpopermittivity

tiro Bohr magneton ]I efl2m Nuclear

IN - en2mmagneton electron g

~value

Schr radius 2 4vm ( Rydber R ml4Shl c

constant

Fine nrucure C= Jloeh2hconstant

Gravitational G ccnSlant

tStandard gIIccelerinion ot free alit

f p n m

femto pico nano micro 10- 1S 10-111 10- 10-middot

Value General data and 2s97 9~42 x 10a m 5- 1 fundamental 160217T)lt) 0-111 C constantsmiddot

S64aS x 10 C mol-I

138066 X 10-1 J Kshy

83451 J 1(-1 mol-I

820578 x 10-2 cm1 atm 1(-1 mol-

62364 L TQrr 1(-1 mol

6526 as x 10---)1 J s

105457)c 10-)1 J oS 602214 x 1012 mol-I

1660 54 x 10-z kg

9109351 x 10-11 kg

167262 X 10-zr kg

middot167493 x Omiddotzr kg

4Jr Xmiddot 0-- J r C-2 m-r 4nx lomiddot7 T2J- ml

B8S4 19 X10-12J~1 C2 m-1

126Sx 1c-tG rIC2m-1

927402 x 10-10amp J T- SOSO 79 x 1o-zrJ I~

2C02~2

529~77 X 10-11 m

1091 37x 10cm-

7297 isx 10-3

65725S x la-II N m Zlcg-Z

bull aSOS 65Jil-~

r Exct Idilo Vllu

c d M G Prefixes deci kilo mega glgl

10-1 10 10middot 105

Confidence Levels for Various Values middotofz

Confidence Level J z

-50

68 i

8amp

067

100

128

I

I I

shy

90

-

164

95 196

954 200

99 258

997 300

999 329

Degrees of Derees offreedom for 5J 1rledom

7 s III f

furl Z ) if 5 Ci ) 10 15 20 pO jQgt

1 190 192 l lQ2 193 193 1~41194 HU lQ4 liU 1M 194 195 195 3 9_~5 9211 i 912 WI 1194 iU9 IlP4 lUI 1179 874 Pi) RM I IUil 853 4 694 659 r 639 626 616 609 604 600 596 591 586 580 ~ 575 563 S 579 HI 519 505 495 4881 482 477 474 46-~ 462 456 i 450 436

6 Sl4 476 53 4J9 41S 421 4lS 41Q 406 400 394 181 1381 367

bull~ 414 435 412 gt97 387 379 373 368 164 353 351 ~A4 i 138 323 8 446 407 384 369 358 350 344 339 335 32S 122 31S i 308 293

9 426 186 )() 348 JJ7 129 323 3l8 314 3U7 lUl 294 I 286 271 Hl f-lt-4IO 371 l 343 333 3~ 314 301 Hi 293 291 284shy 271 2711 bull 254-__- _--_ _- I-shy --shy ---shy --_ - -~r-middot---middot middot __shyII 398 359 ~ 336 320 310 301 295 290 285 279 272 265 257 240- 2S4111 38 349 126 II 300 291 28S 280 275 260) 162 247 23(1

1 HI )41 i ItA Hi 1 92 Ul li7 lil -67 2M -~t -4Q 2 I~ 14 374 334 bull 311 296 21 276 270 16$ ltiO 251 246 239 [ 131 213 15 J()~ 3l~ 3Jl6 2Kl 271) 271 L2~ 159 254 24-~ 240 ali 225 ---shy -16 l6 324 1111 285 274 Vi( 2jil 250 249 242shy 2Ji 22R I 219 201 ]7 3J9 3W 296 281 270 261 255 249 245 23~ ln un Hi 196

219 t18 ~_6 SII) 293 11 2fi6 ]8 151 246 241 234 217 211 192 19 35 lnf 290 274 263 254shy l48 242 238 231 223 216 I201 188 20 349 lLO t 2$1 271 260 251 245 239 235 22~ 220 212 204 184 30 332 292 269 253 242 233 221 221 116 209 201 193 JS4 162 0 300 260 lJ7 221 lJO 201 194 1amp8 U3 J7~ 167 157 14( 100

USEFUL CONSTANTS

Ka Acid Base Name Formula Formula Name

Large Perchloric acid HCI04 CI04shy Perchlorate ion 32 10~ Hydroiodic acid HI 1shy Iodide 10 10~ Hydrobromic acid HBr Br- Bromide 13 lOb Hydrochloric acid HCI CI- Chloride 10 103 Sulfuric acid H2SO4 HS04shy Hydrogen sulfate ion 24 101

-Nitric acid RN03 N03shy Nitrate ion

-------shy Hydronium ion H3O+ H2O Water

~

Ka shy- - Acid Conjugate Base

Name Formula Formula Name Large -

Perchloric acid HCI04 CI04shy Perchlorate ion 32 10~ Hydroiodic acid HI 1shy Iodide 10 109 Hydrobromic acid HBr Br- Bromide 13 lOb Hydrochloric acid HCI CI- Chloride 10103 Sulfuric acid H2SO4 HS04shy Hydrogen sulfate ion 24 101 Nitric acid HN03 N03shy II Nitrate ion -------shy Hydronium ion H3O+ H2O Water

54 1O-l Oxalic acid H02C20 2H H02C20 2shy Hydrogen oxalate ion 13 1O-l Sulfurous acid H2S03 HS03shy Hydrogen sulfite ion 10 10-2 Hydrogen sulfate ion HS04shy S04 2- Sulfate ion 71 10-3 Phosphoric acid H3P04 H2P04- Dihydrogen phosphate

ion 72 10-4 Nitrous acid HN02 N03shy Nitrite ion 66 10-4 Hydrofluoric acid HF F- Fluoride ion 18 10-4 Methanoic acid HC02H HC02shy Methanoate ion 63 10- Benzoic acid C6HsCOOH C6HsCOOshy Benzoate ion 54 10- Hydrogen oxalate ion H02C20~- 02C20 2 ~- Oxalate ion 18 10- Ethanoic acid CH3COOH CH3COO Ethanoate (acetate)

ion 44 10- 1 Carbonic acid C03lshy HC03shy Hydrogen carbonate

ion 11 10-7 Hydrosulfuric acid H2S HS- Hydrogen sulfide ion 63 1O-~ Dihydrogen phosphate

ion H2P04shy HP04l- Hydrogen phosphate

ion 62 10-8 Hydrogen sulfite ion -lISshy S2shy Sulfite ion 29 10-~ Hypochlorous acid HCIO CIO- Hypochlorite ion 62 10-10 Hydrocyanic acid HCN CN- Cyanide ion 58 lO- IU Ammonium ion NH4 + NH3 Ammonia 58 10-10 Boric acid H3B03 H2Bq3 - Dihydrogen carbonate

ion 47 10-11 Hydrogen carbonate ion HC03shy C03 l- Carbonate ion 42 lO- lJ

Hydrogen phosphate ion

HP04lshy P04-shy Phosphate ion

18 10-13 Dihydrogen borate ion H2B03- HB03l- Hydrogen borate ion 13 10-1- Hydrogen sulfide ion HSshy S ~- Sulfide ion 16 10-14 Hydrogen borate ion HB03

2- B033shy Borate ion --------shy water H2O OH- Hydroxide

I

j 4

-f

I to

Ouantil Symbol r

Speed of lighr c Elemlfmary e

charge

Faraday F=eNI COMstanc

BoltzrTinn k cons3Ct

Gas costant n=kNA

PlancK constant h

h-h2T Avogadro Ni

constant

Atomic mass u unit

Mass of Iectron m proton m neutron m

Vacuum 1 permeabilityt

VaCtum r-lrrpopermittivity

tiro Bohr magneton ]I efl2m Nuclear

IN - en2mmagneton electron g

~value

Schr radius 2 4vm ( Rydber R ml4Shl c

constant

Fine nrucure C= Jloeh2hconstant

Gravitational G ccnSlant

tStandard gIIccelerinion ot free alit

f p n m

femto pico nano micro 10- 1S 10-111 10- 10-middot

Value General data and 2s97 9~42 x 10a m 5- 1 fundamental 160217T)lt) 0-111 C constantsmiddot

S64aS x 10 C mol-I

138066 X 10-1 J Kshy

83451 J 1(-1 mol-I

820578 x 10-2 cm1 atm 1(-1 mol-

62364 L TQrr 1(-1 mol

6526 as x 10---)1 J s

105457)c 10-)1 J oS 602214 x 1012 mol-I

1660 54 x 10-z kg

9109351 x 10-11 kg

167262 X 10-zr kg

middot167493 x Omiddotzr kg

4Jr Xmiddot 0-- J r C-2 m-r 4nx lomiddot7 T2J- ml

B8S4 19 X10-12J~1 C2 m-1

126Sx 1c-tG rIC2m-1

927402 x 10-10amp J T- SOSO 79 x 1o-zrJ I~

2C02~2

529~77 X 10-11 m

1091 37x 10cm-

7297 isx 10-3

65725S x la-II N m Zlcg-Z

bull aSOS 65Jil-~

r Exct Idilo Vllu

c d M G Prefixes deci kilo mega glgl

10-1 10 10middot 105

Degrees of Derees offreedom for 5J 1rledom

7 s III f

furl Z ) if 5 Ci ) 10 15 20 pO jQgt

1 190 192 l lQ2 193 193 1~41194 HU lQ4 liU 1M 194 195 195 3 9_~5 9211 i 912 WI 1194 iU9 IlP4 lUI 1179 874 Pi) RM I IUil 853 4 694 659 r 639 626 616 609 604 600 596 591 586 580 ~ 575 563 S 579 HI 519 505 495 4881 482 477 474 46-~ 462 456 i 450 436

6 Sl4 476 53 4J9 41S 421 4lS 41Q 406 400 394 181 1381 367

bull~ 414 435 412 gt97 387 379 373 368 164 353 351 ~A4 i 138 323 8 446 407 384 369 358 350 344 339 335 32S 122 31S i 308 293

9 426 186 )() 348 JJ7 129 323 3l8 314 3U7 lUl 294 I 286 271 Hl f-lt-4IO 371 l 343 333 3~ 314 301 Hi 293 291 284shy 271 2711 bull 254-__- _--_ _- I-shy --shy ---shy --_ - -~r-middot---middot middot __shyII 398 359 ~ 336 320 310 301 295 290 285 279 272 265 257 240- 2S4111 38 349 126 II 300 291 28S 280 275 260) 162 247 23(1

1 HI )41 i ItA Hi 1 92 Ul li7 lil -67 2M -~t -4Q 2 I~ 14 374 334 bull 311 296 21 276 270 16$ ltiO 251 246 239 [ 131 213 15 J()~ 3l~ 3Jl6 2Kl 271) 271 L2~ 159 254 24-~ 240 ali 225 ---shy -16 l6 324 1111 285 274 Vi( 2jil 250 249 242shy 2Ji 22R I 219 201 ]7 3J9 3W 296 281 270 261 255 249 245 23~ ln un Hi 196

219 t18 ~_6 SII) 293 11 2fi6 ]8 151 246 241 234 217 211 192 19 35 lnf 290 274 263 254shy l48 242 238 231 223 216 I201 188 20 349 lLO t 2$1 271 260 251 245 239 235 22~ 220 212 204 184 30 332 292 269 253 242 233 221 221 116 209 201 193 JS4 162 0 300 260 lJ7 221 lJO 201 194 1amp8 U3 J7~ 167 157 14( 100

USEFUL CONSTANTS

Ka Acid Base Name Formula Formula Name

Large Perchloric acid HCI04 CI04shy Perchlorate ion 32 10~ Hydroiodic acid HI 1shy Iodide 10 10~ Hydrobromic acid HBr Br- Bromide 13 lOb Hydrochloric acid HCI CI- Chloride 10 103 Sulfuric acid H2SO4 HS04shy Hydrogen sulfate ion 24 101

-Nitric acid RN03 N03shy Nitrate ion

-------shy Hydronium ion H3O+ H2O Water

~

Ka shy- - Acid Conjugate Base

Name Formula Formula Name Large -

Perchloric acid HCI04 CI04shy Perchlorate ion 32 10~ Hydroiodic acid HI 1shy Iodide 10 109 Hydrobromic acid HBr Br- Bromide 13 lOb Hydrochloric acid HCI CI- Chloride 10103 Sulfuric acid H2SO4 HS04shy Hydrogen sulfate ion 24 101 Nitric acid HN03 N03shy II Nitrate ion -------shy Hydronium ion H3O+ H2O Water

54 1O-l Oxalic acid H02C20 2H H02C20 2shy Hydrogen oxalate ion 13 1O-l Sulfurous acid H2S03 HS03shy Hydrogen sulfite ion 10 10-2 Hydrogen sulfate ion HS04shy S04 2- Sulfate ion 71 10-3 Phosphoric acid H3P04 H2P04- Dihydrogen phosphate

ion 72 10-4 Nitrous acid HN02 N03shy Nitrite ion 66 10-4 Hydrofluoric acid HF F- Fluoride ion 18 10-4 Methanoic acid HC02H HC02shy Methanoate ion 63 10- Benzoic acid C6HsCOOH C6HsCOOshy Benzoate ion 54 10- Hydrogen oxalate ion H02C20~- 02C20 2 ~- Oxalate ion 18 10- Ethanoic acid CH3COOH CH3COO Ethanoate (acetate)

ion 44 10- 1 Carbonic acid C03lshy HC03shy Hydrogen carbonate

ion 11 10-7 Hydrosulfuric acid H2S HS- Hydrogen sulfide ion 63 1O-~ Dihydrogen phosphate

ion H2P04shy HP04l- Hydrogen phosphate

ion 62 10-8 Hydrogen sulfite ion -lISshy S2shy Sulfite ion 29 10-~ Hypochlorous acid HCIO CIO- Hypochlorite ion 62 10-10 Hydrocyanic acid HCN CN- Cyanide ion 58 lO- IU Ammonium ion NH4 + NH3 Ammonia 58 10-10 Boric acid H3B03 H2Bq3 - Dihydrogen carbonate

ion 47 10-11 Hydrogen carbonate ion HC03shy C03 l- Carbonate ion 42 lO- lJ

Hydrogen phosphate ion

HP04lshy P04-shy Phosphate ion

18 10-13 Dihydrogen borate ion H2B03- HB03l- Hydrogen borate ion 13 10-1- Hydrogen sulfide ion HSshy S ~- Sulfide ion 16 10-14 Hydrogen borate ion HB03

2- B033shy Borate ion --------shy water H2O OH- Hydroxide

I

j 4

-f

I to

Ouantil Symbol r

Speed of lighr c Elemlfmary e

charge

Faraday F=eNI COMstanc

BoltzrTinn k cons3Ct

Gas costant n=kNA

PlancK constant h

h-h2T Avogadro Ni

constant

Atomic mass u unit

Mass of Iectron m proton m neutron m

Vacuum 1 permeabilityt

VaCtum r-lrrpopermittivity

tiro Bohr magneton ]I efl2m Nuclear

IN - en2mmagneton electron g

~value

Schr radius 2 4vm ( Rydber R ml4Shl c

constant

Fine nrucure C= Jloeh2hconstant

Gravitational G ccnSlant

tStandard gIIccelerinion ot free alit

f p n m

femto pico nano micro 10- 1S 10-111 10- 10-middot

Value General data and 2s97 9~42 x 10a m 5- 1 fundamental 160217T)lt) 0-111 C constantsmiddot

S64aS x 10 C mol-I

138066 X 10-1 J Kshy

83451 J 1(-1 mol-I

820578 x 10-2 cm1 atm 1(-1 mol-

62364 L TQrr 1(-1 mol

6526 as x 10---)1 J s

105457)c 10-)1 J oS 602214 x 1012 mol-I

1660 54 x 10-z kg

9109351 x 10-11 kg

167262 X 10-zr kg

middot167493 x Omiddotzr kg

4Jr Xmiddot 0-- J r C-2 m-r 4nx lomiddot7 T2J- ml

B8S4 19 X10-12J~1 C2 m-1

126Sx 1c-tG rIC2m-1

927402 x 10-10amp J T- SOSO 79 x 1o-zrJ I~

2C02~2

529~77 X 10-11 m

1091 37x 10cm-

7297 isx 10-3

65725S x la-II N m Zlcg-Z

bull aSOS 65Jil-~

r Exct Idilo Vllu

c d M G Prefixes deci kilo mega glgl

10-1 10 10middot 105

Ka Acid Base Name Formula Formula Name

Large Perchloric acid HCI04 CI04shy Perchlorate ion 32 10~ Hydroiodic acid HI 1shy Iodide 10 10~ Hydrobromic acid HBr Br- Bromide 13 lOb Hydrochloric acid HCI CI- Chloride 10 103 Sulfuric acid H2SO4 HS04shy Hydrogen sulfate ion 24 101

-Nitric acid RN03 N03shy Nitrate ion

-------shy Hydronium ion H3O+ H2O Water

~

Ka shy- - Acid Conjugate Base

Name Formula Formula Name Large -

Perchloric acid HCI04 CI04shy Perchlorate ion 32 10~ Hydroiodic acid HI 1shy Iodide 10 109 Hydrobromic acid HBr Br- Bromide 13 lOb Hydrochloric acid HCI CI- Chloride 10103 Sulfuric acid H2SO4 HS04shy Hydrogen sulfate ion 24 101 Nitric acid HN03 N03shy II Nitrate ion -------shy Hydronium ion H3O+ H2O Water

54 1O-l Oxalic acid H02C20 2H H02C20 2shy Hydrogen oxalate ion 13 1O-l Sulfurous acid H2S03 HS03shy Hydrogen sulfite ion 10 10-2 Hydrogen sulfate ion HS04shy S04 2- Sulfate ion 71 10-3 Phosphoric acid H3P04 H2P04- Dihydrogen phosphate

ion 72 10-4 Nitrous acid HN02 N03shy Nitrite ion 66 10-4 Hydrofluoric acid HF F- Fluoride ion 18 10-4 Methanoic acid HC02H HC02shy Methanoate ion 63 10- Benzoic acid C6HsCOOH C6HsCOOshy Benzoate ion 54 10- Hydrogen oxalate ion H02C20~- 02C20 2 ~- Oxalate ion 18 10- Ethanoic acid CH3COOH CH3COO Ethanoate (acetate)

ion 44 10- 1 Carbonic acid C03lshy HC03shy Hydrogen carbonate

ion 11 10-7 Hydrosulfuric acid H2S HS- Hydrogen sulfide ion 63 1O-~ Dihydrogen phosphate

ion H2P04shy HP04l- Hydrogen phosphate

ion 62 10-8 Hydrogen sulfite ion -lISshy S2shy Sulfite ion 29 10-~ Hypochlorous acid HCIO CIO- Hypochlorite ion 62 10-10 Hydrocyanic acid HCN CN- Cyanide ion 58 lO- IU Ammonium ion NH4 + NH3 Ammonia 58 10-10 Boric acid H3B03 H2Bq3 - Dihydrogen carbonate

ion 47 10-11 Hydrogen carbonate ion HC03shy C03 l- Carbonate ion 42 lO- lJ

Hydrogen phosphate ion

HP04lshy P04-shy Phosphate ion

18 10-13 Dihydrogen borate ion H2B03- HB03l- Hydrogen borate ion 13 10-1- Hydrogen sulfide ion HSshy S ~- Sulfide ion 16 10-14 Hydrogen borate ion HB03

2- B033shy Borate ion --------shy water H2O OH- Hydroxide

I

j 4

-f

I to

Ouantil Symbol r

Speed of lighr c Elemlfmary e

charge

Faraday F=eNI COMstanc

BoltzrTinn k cons3Ct

Gas costant n=kNA

PlancK constant h

h-h2T Avogadro Ni

constant

Atomic mass u unit

Mass of Iectron m proton m neutron m

Vacuum 1 permeabilityt

VaCtum r-lrrpopermittivity

tiro Bohr magneton ]I efl2m Nuclear

IN - en2mmagneton electron g

~value

Schr radius 2 4vm ( Rydber R ml4Shl c

constant

Fine nrucure C= Jloeh2hconstant

Gravitational G ccnSlant

tStandard gIIccelerinion ot free alit

f p n m

femto pico nano micro 10- 1S 10-111 10- 10-middot

Value General data and 2s97 9~42 x 10a m 5- 1 fundamental 160217T)lt) 0-111 C constantsmiddot

S64aS x 10 C mol-I

138066 X 10-1 J Kshy

83451 J 1(-1 mol-I

820578 x 10-2 cm1 atm 1(-1 mol-

62364 L TQrr 1(-1 mol

6526 as x 10---)1 J s

105457)c 10-)1 J oS 602214 x 1012 mol-I

1660 54 x 10-z kg

9109351 x 10-11 kg

167262 X 10-zr kg

middot167493 x Omiddotzr kg

4Jr Xmiddot 0-- J r C-2 m-r 4nx lomiddot7 T2J- ml

B8S4 19 X10-12J~1 C2 m-1

126Sx 1c-tG rIC2m-1

927402 x 10-10amp J T- SOSO 79 x 1o-zrJ I~

2C02~2

529~77 X 10-11 m

1091 37x 10cm-

7297 isx 10-3

65725S x la-II N m Zlcg-Z

bull aSOS 65Jil-~

r Exct Idilo Vllu

c d M G Prefixes deci kilo mega glgl

10-1 10 10middot 105

I

j 4

-f

I to

Ouantil Symbol r

Speed of lighr c Elemlfmary e

charge

Faraday F=eNI COMstanc

BoltzrTinn k cons3Ct

Gas costant n=kNA

PlancK constant h

h-h2T Avogadro Ni

constant

Atomic mass u unit

Mass of Iectron m proton m neutron m

Vacuum 1 permeabilityt

VaCtum r-lrrpopermittivity

tiro Bohr magneton ]I efl2m Nuclear

IN - en2mmagneton electron g

~value

Schr radius 2 4vm ( Rydber R ml4Shl c

constant

Fine nrucure C= Jloeh2hconstant

Gravitational G ccnSlant

tStandard gIIccelerinion ot free alit

f p n m

femto pico nano micro 10- 1S 10-111 10- 10-middot

Value General data and 2s97 9~42 x 10a m 5- 1 fundamental 160217T)lt) 0-111 C constantsmiddot

S64aS x 10 C mol-I

138066 X 10-1 J Kshy

83451 J 1(-1 mol-I

820578 x 10-2 cm1 atm 1(-1 mol-

62364 L TQrr 1(-1 mol

6526 as x 10---)1 J s

105457)c 10-)1 J oS 602214 x 1012 mol-I

1660 54 x 10-z kg

9109351 x 10-11 kg

167262 X 10-zr kg

middot167493 x Omiddotzr kg

4Jr Xmiddot 0-- J r C-2 m-r 4nx lomiddot7 T2J- ml

B8S4 19 X10-12J~1 C2 m-1

126Sx 1c-tG rIC2m-1

927402 x 10-10amp J T- SOSO 79 x 1o-zrJ I~

2C02~2

529~77 X 10-11 m

1091 37x 10cm-

7297 isx 10-3

65725S x la-II N m Zlcg-Z

bull aSOS 65Jil-~

r Exct Idilo Vllu

c d M G Prefixes deci kilo mega glgl

10-1 10 10middot 105

~-=-- ---shy

( l (

PERIODIC TABLE OF ELEMENTS bull

GROUPS

l)Cmliilildtlriintrshiumfrer oflli~ irtJ(vpl willi fhd IOl7gest hOflifl

Ibull

2 [J-T4 1_ 5 I 6 7 I 8 t -~~ 1 IO~_I Trr2-T- iii r]~~J lrJ 1pound J c~1 a =~ ~1L jjj~liL ~_j1_ IIIUOUS IA IIA I 11111 I IVIl1 VI)I-vm-T--vml-~- VIIfl --r III -r-itl) --1I16J IVA VA LyrA Lvlt~ y1JJA

2

J

4

5

1lInK II

I 61941 Li 3

902 Dc 4 - S-~i middot~rlmiddotmiddot I

Atomic No 5 6 1

ft22990 1240305 Nn Mg II 12

TRANSITION ELEMENTS

39i~9r fbbYIi 96478 5042 S096114~9JII S5841 15 bullbull 9]] 1869163461639 K ~ bull TI V ~ bull ~ ~ M ~ ~ 19 20 21 22 II 24 lS 26 27 2 29 10

2MI~ -28paG 30974

I~~~middotI~1middotI~~~~middotI~~Imiddot~6-~ 1~~ 19~9~-middotImiddot~middot~RI-~middotrmiddot~)9111~~2110Amiddot8711Ii41Id Sr T Zr N 110 Ie II ~I lU It Cd )7 38 39 40 41 42 43 44 u 46 47 41

In

19508 19697 200S9 P-i Au Hg 18 79 BO

c(1) UUH 110

I] 14 15

9723 17261

1142 11111

TI

Al SI P

Gs Gc 31 12

So 49 SO

20438 2072 SI

Pb 82 Di

741922 As Jl

12175 Sb

20898

81

_~ __zoMtotI~ ~ofX~ da~ ~~~~t~~~~~~ntwtraquobullbullbullU~~~~-J~L~~ _ __~

bull~nnUUll1idsSelies

tt Adinli~le Series I ~

mll Hi 2

rs IfsectffI[ll0 o F Ne a 9 10

J2~06 JS~jJ)~1 S CI Ar 16 11 II

7196 79904 IJ~O Se Dr lr 34 lS 36

r2760 12690middot 1J129

Te I Xc S2 5] -1

(209) (210) (222) 10 At fln 84 85 _~ 86

litHi ~ 1J1-shy

I~O91

fr 59 ~

1~24

Jt4 6ck

(145)

em 61

15016 $tn 62

15196 Eu 63

IS1lS Gd 64

15amp93 Tb 65

16250 Dy 66

16493 flo 67

16726

Er 68

16amp93

Tm 69

7304

Yb 70

17497 LII 71

111)04 ~)~

-~c

2JJ 114 -iek C ~~

2lIJItJ ~U- J~

21105 JNjh -~

(2) -u 24

(243) Am ~S

(247) em

96

(241) DIt 91

(25 cr 9i

(252)-Es 91

(257) Fill 100

(2S8)

Md 1Of

(259)

No 102

(260)

Lr 103