b. 1000 m = 1 km 109 m3 = 1 km3c. 10 mm = 1 cm 1000 mm3 = 1 cm3d. 10 cm =; 1 dm 1000 cm3 = 1 dm3

CRflVfcfL (Review, page 211. Religion and philosophy; other answers are pos¬

sible.

. Interpretations of events are influenced so muchby what we know and believe that science insiststhat different individuals must make independentobservations and reach similar conclusions be¬fore something is accepted as fact. Unless the firstobserver can communicate exactly what wasdone to make an observation, an independentobserver will not be able to repeat an experimentor observation.

3. Whenever possible, they express regularities asmathematical equations. Graphs, tables, draw¬ings, and photographs are also used. In any com¬munication, they separate observations frominferences based on those observations.

4. What we observe and how we interpret it is influ¬enced by what we already know and believe.Since no two people are likely to know and believeexactly the same things, the more people whoagree about what happened, the more likely itactually happened.

5. It takes up space and has mass.

. It does not take up space or have mass. Some ex¬

periments suggest that light does have mass, butit is extremely small.

7. Mass is a property of matter that gives it weightand inertia. Inertia is the resistance of matter tochange, i.e., being stopped or being moved. Theheavier an object is, the more inertia it has; themore inertia it has, the more mass it has. To saymatter has mass means that matter has inertiaand requires a force to get it moving or stopped.Force is the energy needed to bring about achange.

8. classification

9. Plasmas have all the properties of gases exceptthat they are composed of charged particles likeelectrons rather than uncharged atoms or mole¬cules.

10. Potential energy was invented to preserve the be¬lief that energy is never created or destroyed; itonly is changed from one form to another. It isbased on the observation of the potential forchanging matter that exists in such things as coalor wood or an unused battery.

11. A quantity is composed of a number and an asso¬ciated unit. Numbers describe amount, but not

the nature of what is described. Quantities de¬scribe both amount and kind of what is observed.

12. Unlike quantities can not be added,

13. metre

14. kilogram

15. A unitary rate is a ratio of quantities. It always hasa denominator of one plus the appropriate unit.Other ratios may only include numbers and thedenominator may have any value.

16. 1

Interpret and Apply, page 211. Teachers and parents are normally older, and

they have experienced different things in theirlives than you have experienced in yours.Whether they are actually wiser as well as older isopen to debate, but the differences in experienceaccount for many disagreements!

2. People of the same age, people from similar homeenvironments, and people from the same countryare more likely to agree. The reasoning is that theyare more likely to have similar experiences, andthe experiences we have determine how we inter¬pret events today.

3. The same point can be made by playing a gamesometimes played by parents and their childrenor teachers and their pupils. The game is to doexactly what the person told us to do but notwhat we are pretty sure the person intended us todo! The point of both exercises is that communi¬cation is very difficult. We must work hard to ex¬press ideas so there is no doubt about what isintended.

4. A mass in space will still have inertia. A springscale could be used to exert a force for a meas¬ured time. Measuring the change in velocity of theobject would produce a measure of mass.

5. sublimation, the transition from solid to gas

6. The assumption that matter is neither created nordestroyed during any of its transformationswould be violated.

7. Kinetic energy is the product of one half the massof the object and its velocity squared. The truckhas more mass; consequently, it has more kineticenergy.

8. The car could have more energy if it were movingmuch faster than the truck.

9. At the time this book was written, the exchangerate was approximately 0.70 Canadian dollars/1U.S. dollar.

10. Place the 50-pound mass on the scale and seewhat it reads. If the scale is calibrated correctly, itshould read 50 pounds. Now place the 20 kilo¬gram mass on the scale and get the reading. It

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CMfiPvez. <should read 44 pounds. Then 20 kg = 44 lb. Divid¬ing each side of the equation by 44, 0.45 kg = 1 lb.The unitary rate is 0.45 kg/lb.

Problems, page 221. The new kinetic energy is { the original.

2. # shoulder to wrist + # wrist to fingertip = # fromshoulder to fingertip

3. # shoulder to wrist + # wrist to fingertip = # fromshoulder to fingertip

4. a. millimetreb. megametrec. kilometred. kilograme. centigramf. microgramg. megagram

5. a. example givenb. 1 Mm = 1000 000 m; 0.000 001 Mm = 1 mc. 1 km = 1000 m; 0.001 km = 1 md. 1 kg = 1000 g; 0.001 kg = 1 ge. 1 eg = 0.01 g; 100 cg = lgf. 1 fxg - 0.000 001 g; 1 000 000 /xg = 1 gg. 1 Mg = 1000 000 g; 0.000 001 Mg = 1 gh. 1 mg = 0.000 001 g; 1000 000 mg = 1 g1. 1 dm = 0.1 m; 10 dm = 1 m

j- 1 dm3 = 0.001 m3; 1000 dm3 = 1 m3k. 1 m3 is the base unit.1. 1 cm3 = 0.000 001 m3; 1000 000 cm3 = 1 m3m. 1 mm2 = 0.000 001 m2; 1000 000 mm2 = Tm;n. 1 km2 = 1000 000 m2; 0,000 001 km2 = 1 m2

6. a. 570 g = 57 dagb. 37 000 mg = 37 gc. 4 700 g = 4.7 kgd. 0.138 km = 138 m . "

e. 4.021 m = 4 021 mmf. 27 000 000 m = 27 Mm

g< 4.62 g = 462 egh. 0.014 g = 14 000 figi. 3.7 X 10" pm = 37 cm

j- 3.2 km = 3 200 000 mm

7. a. 1000 000 mm2 = 1 m2b. 0.000 001 km2 = 1 m2c. 0.01 cm2 = 1mm2d. 1000 000 /xm2 = 1 mm2e. 0.000 001 Mm2 = 1 km2f. 0.001 cm3 = 1 mm3

g- 0.000 001 m3 = 1 cm3h. 10-9 km3 = 1 m3

i. 1000 dm3 = 1 m3

j- 1012 /xm3 = 1 cm3

8. a. 0.005 280 m2 = 5 280 mm2

b. 2.5 X 106 m2 = 2.5 km2

c. 4.53 x io4 mm2 = 453 cm2 '

d. 9.055 033 mm2 = 9 055 033 /xm2e. 25 km2 = 0.000 025 Mm2f. 1.23 X 10s mm3 = 123 cm3

g. 0.005 345 m3 = 5 345 cm3h. 4.6 X io7m3 = 0.046 km3

i. 1.000 m3 = 1000 dm3j. 3.098 000 X IO"6 cm3 = 3 098 000 fim3

9. b and c

Challenge, page 22 _1. Answers will vary. Such an experiment would need

to include the measurement of the amount of food,water, and air ingested; measurement of solid, liq¬uid, and gaseous wastes from digestive, urinary,and respiratory systems and also the skin; meas¬urement of body growth and development, tissuerepair and replacement, energy released from food;measurement of body synthesis of substances suchas emymes and hormones.

2. Measure any length in both inches and centime¬ters. Divide the length in centimeters by the lengthin inches. The result should be 2.54 cm/in withinthe uncertainty of the measurements done.

3. 16.4 cm3 = 1 in3

4. 10-18 Em = 1 m; 1018 am = 1 m

Then ICT18 Em = 1018 am1 Em = 1036 am

5. 1 Em = 1018 m

1 Em3 = 1054 m3

The volume of a sphere is Jtt r3or iir d3.

Given the diameter of Earth as 1.27 X 104km3 andassuming that Earth is a perfect sphere:V = $77(1.27 Xl07m3)V = 1.07 X 1021m3

One Em3 is far greater than the volume of Earth.6. lam = 10~18m

lam3 = 10~54 m3

The Bragg-Slater radius of the hydrogen atom is25 pm (25 X 10-12 m). Then the volume of a hydro¬gen atom is:V = 377r3

V = $77(2.5 X IO-11 m3)V = 6.5 X I0~32m3

One am3 is much smaller than the volume of thesmallest atom.

h. milligrami. decimetrej. cubic decimetrek. cubic metre1. cubic centimetrem. square millimetren. square kilometre

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"CHftPTZZ. Q

6. a. Ca(C2H302)2 e. AKOH^b. Na3P04 f. Ca(HC03)2C. CUSO4 g- (NH4}3P04d. Fe3(P04)2 h. LizCrzOv

7. a. aluminum nitrate

b. hydrogen carbonatec. tindl) nitrated. potassium dichromatee. copper(I) carbonatef. ammonium chlorideg. nickeKD oxalate

Review, page 571. Shine a strong light through a sample of the soft

drink to see if light is scattered by particles in sus¬pension. You also can allow the soft drink to standfor a period of time to see if matter settles out, ordistill it to separate the mixture.

2. a. Distillation will work.b. Distillation will work to a point, but it will not

produce a total separation. Students are un¬likely to know any of the procedures that pro¬duce a total separation.

c. If the pieces are large, simply pick them out byhand. If they are small, use a magnet to attractthe iron.

d. Add water. The sugar will dissolve; the glasswill not. The sugar can be recovered by boilingaway the water.

e. It is possible to make a liquid that has a higherdensity than the aluminum but a lower densitythan the zinc. The aluminum would float onthe liquid, but the zinc would sink. Studentsare unlikely to know about this procedure. Thequestion is asked to make^he point that it isoften difficult to separate mixtures, even whenthe pieces are large.

SET I3. potassium

4. Hg

St Znl2

6. Ag20

SET H7. bromine

8. Cu

9. PCI5

10. SO3

SET in11. Pb

13. gold

13. NiB

14. Lil

Interpret and Apply, page 581. a. Chemical—the color change suggests that new

compounds are formed.b. Physical—breaking things is considered to be a

physical change because characteristic proper¬ties such as density, melting point, boilingpoint, ignition temperature, and color are un¬changed.

c. Physical—solution is normally considered to bea physical change, because it can be easily re¬versed by boiling away the solvent.

d. Chemical—without knowing exactly how aspi¬rin works, we cannot be sure, but it seems like areasonable guess that some new substance isformed in the process.

e. Physical—the water molecules remain intact.Phase changes such as this change from liquidto gas are normally considered to be physical.

f. Chemical—the properties of cooked beans areclearly different from the properties of un¬cooked beans. For example, the taste ischanged.

g. Chemical—new cells are being produced in thegrass, and water and carbon dioxide react in theprocess.

h. Physical—like b, big pieces are made intosmaller pieces.

i. Chemical—you may have difficulty making thisjudgment, but the bleach reacts with stains toproduce new compounds that dissolve in thewater to be washed away.

j. Both—the Drano reacts with fats to producesoaps. The aluminum flakes in the Drano reactto produce hydrogen gas. These changes arechemical. The agitation caused by the hydrogengas and the rise in temperature that melts thefats in the drain are physical changes that helpunstop the sink.

3. a. The decrease in mass of the solid and the pro¬duction of the gas lead me to believe that this isa compound that is decomposing.

b. The increase in mass suggests that the metalhas combined with something in the air, possi¬bly an element.

c. The decrease in mass suggests that some matterhas left the log. Probably compounds in the logdecomposed to form gases that escaped. Closeinspection may show that some of the log wastaken away in the digestive tracts of small ani¬mals, a physical change followed by a chemicalchange.

d. This suggests that the black powder combinedwith the oxygen to form the colorless gas. Theblack powder probably is an element, and theproduct is a compound.

e. If there were only one product, this could be anelement that combines with oxygen gas to pro¬duce a compound. Since three products areformed, it seems more likely that the originalsolid was a compound that reacted with oxygento produce several different products. This re¬sult also could come from an element reactingwith oxygen, but since elements combine toform compounds with a definite composition,the three different products are more likely toresult from reaction with a compound contain¬ing several elements than from a single element.

3. No. Compounds have a definite composition. The

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CMftfTefL O.two solids could be mixtures containing copper orthey could be two compounds containing copper.

4. Not necessarily. Copper may form ions with a 1+charge or ions with a 2+ charge. Copper can formwo compounds with chlorine. You must knowihat the percent of copper in the two samples isthe same before concluding that the samples are ofthe same compound.

5. No. Pure compounds have the characteristics de¬scribed. It could be an element or a compound.

6. Heat it and see if you get a new substance. If youdo, see if the new substance weighs more or lessthan the original substance. If nothing comes fromheating it, try melting it and passing an electriccurrent from a battery through the liquid. If newsubstances form at the two electrodes, it is proba¬bly a compound.

7. a. See Figure 2-22c.

b. See Figure 2-22a.c. See Figure 2-23b.d. See Figure 2-17.e. Make a drawing like Figure 2-17, but show pairs

of atoms connected rather than individualatoms. Like Figure 2-17, these pairs of atoms(molecules) would be close together but not inan ordered array.

8. a.

•• ©® @©®

Problems, page 581. a. AICI3

b. aluminum sulfidec. mercuiy(II) oxide

2. a. dinitrogen trioxideb. FeCl2c. MgaNad. chromium(III) oxide

3. a. KBr

b. silicon carbide; monosilicon monocarbidec. SC12d. tin(IV) oxide

d. CoCl2e. carbon disulfidef. N204

e. manganese dioxide;manganese(IV) oxide

f. C0F3

e. carbon tetrachloridef. AlN

4. a. BaaN;.

b. calcium carbideCalcium dicarbide would be a better name,since no rule has been given to predict thenumber of carbon atoms that will combine withcalcium.

c. CraSiaStudents will be unable to predict this formulafrom the rules given, The rules given enable usto predict the names of most common com¬pounds, but additional rules are required beforeone can handle all nomenclature problems. Thepoint made in this text is that systems of no¬menclature do exist. Complete systems are fartoo complex to present in an introductorycourse.

d. cobalt(II) oxidee. CuOf. golddll) bromideg. FeCl3h. tetraboron monocarbidei. NI3j. pentanickel diphosphide

Even though nickel is a metal, this name is bet¬ter than nickel(II) phosphide because we haveno rule that tells what the charge on the phos¬phide ion should be. This compound is, in fact,a covalent compound and should be named asshown, but students have no way of knowingthat.

5. a.

b.

c.

d.

f.

g-h.

i.

j.k.

1.

m,

n.

6. a.

b.

c.

d.

e.

f.

g.

copper(II) phosphatehydrogen sulfiteSuifurous acid is the more common name, butit is not a systematic name.tin(II) chromateiron(II) sulfiteWatch the spelling of sulfite.potassium hydrogen carbonatePotassium bicarbonate is the common name.magnesium carbonatecalcium nitratePb(Cr204)2NaOH{NH4)2C03MgS03Compare this to sulfate and sulfide.MgSMgS04Ca{C2Hg02)2

This is the sulfite ion.sulfur trioxide, a moleculecarbon disulfide, a moleculephosphorus pentoxide, a moleculephosphate ioncarbon monoxide, a moleculecarbonate ion

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cj-iAPizn ah. nitrogen dioxide, a molecule1. nitrite ionj. iron{III) sulfate, a molecule

More correctly, it is an ionic solid, but studentsare unlikely to know this.

Challenge, page 591. and 2. Various maps will be constmcted. Here is

an example. In evaluating students' maps, look tosee that they have made sensible connections be¬tween terms.

matter—solid, liquid, gas

lean be

pure substance

compound element

mixture

solution

elements

decomposes Imade ofto form —atoms

o*

Projects, page 591. Answers will vaiy.

2. Changing the electrodes changes the products. Forexample, graphite electrodes produce some gasother than oxygen, probably carbon monoxide orcarbon dioxide. Copper electrodes react and thesolution turns blue. Some steel electrodes workwell if the electrolyte is sodium carbonate, but notif it is acid or contains chloride ion.

Changing the amount of electrolyte affects thespeed of the reaction. Changing the nature of theelectrolyte changes the products fomzed. For ex¬ample, chloride ion reacts to form chlorine gas orsome compound, depending on the electrodeused.

3. Some of the properties mentioned vary periodi¬cally, but others do not. In no case is the trendperfect.

4. Flotation, salting out, distillation, electrophoresis,paper and column chromatography are a few ofthe techniques that may be discovered.

CHAPTER 3 Numbers Large and Small

1 HUH s| < ||ii\

< HUHiitniu.wi/i it

in mii\ iit\iiM\ \l I IIIMi \1

'Use the Problem-Solving Strategies for students found in the Teacher's Resource Binder.

¦ ObjectivesWhen students have completed this chapter, they

will be able to

1. State whether a relationship is directly propor¬tional, inversely proportional, or neither from atable showing one variable as a function of an¬other.

2. Convert any number from decimal to scientific(exponential) notation, and vice versa. Add, sub¬tract, multiply, or divide numbers written in sci¬entific notation.

3. Describe the uncertainty of a measurement thatthey have made and what is meant by uncertainlyof measurement.

4. Identify the digits that are certain and the one

CMrre^ 3h

page 891. The slope is 3.2 g/penny. It means that on the

average the mass of 1977 pennies increases 3.2 gwith each penny added.The slope is 2.8 g/penny. It means that on theaverage the mass of 1980 pennies increases2.8 g/penny with each penny added.

3. 1977 pennies have more mass than 1980 pennies.They do not have the same mass because they aremade of different materials.

page 90I. 2.17 g/cm3; unitaiy rate

3. 45.6 g

3. 0.35 cm3

4. the golf ball5. The line would lie below the line for glass, i.e., its

slope would be smaller because the density issmaller. The line should pass through the originbecause plastic with no volume should have nomass.

Review, page 911. proportional

3. A/B = k

3. exponent; 4; base

4. 7

to make it easier to detect irregularities

. g/cm3; kg/m3

7. precision, because they want to reduce theamount of uncertainty in the grades

8. accuracy, because there was a mistake in ac¬

cepted values

9. a. 2.7 X 103

b. 2.7 x 103; 27 X 102; 270 X 101c. 2700

10. 2.7 X 103 or 27 X 10zThe other expressions are unacceptable becausethey do not make clear that the measurement isuncertain in the second digit.

II. 0.014 is the relative uncertainty; absolute

13. 7 and 2; 5

13. A small slope means that die roof rises very littlefor its width; it is not steep. A large slope meansthat the roof rises a lot for its width; it is steep. Tocalculate the slope of the roof, measure the hori¬zontal distance from the edge of the roof to apoint directly beneath the ridge of the roof. Mea¬sure the distance from the ridge to this point. Thedistance from the point to the ridge divided bydie horizontal distance to the edge is the slope ofthe roof.

14. A, c, e, and g can be considered to be extensive.

The latter two can be debated. They do not de¬pend on the amount of matter present, althoughthey do depend on the amount of something else.

15. B, d, f, and h can be considered to be intensive.The latter two can be debated for the same reasongiven in question 14.

16. Neither I nor III lists data that are proportional.The data in II are direcdy proportional. The data

' in IV are inversely proportional.

Interpret and Apply, page 921-4. These questions require individual attention.

5. Probably not. The data represent measurements,and they contain uncertainty. The graph should bedrawn to average out the uncertainty.

6. You could not simply look to see which lookedsteeper, because you may have used differentscales. However, if you examined the scales care¬

fully, you might be able to tell without actuallydoing a calculation.

7. There is uncertainty in both their measurementsand their estimations.

8. There is uncertainty in measurement and fluctua¬tions in conditions from one cooking session toanother. For example, the relative humidity andthe temperature of the room could affect somedishes.

Problems, page 921. 6; 1012

3. 2.5 m in diameter; 2.5 km in diameter

3. 0.0012 mm; 0.0001mm

4. 1.18 X 10~23 cm3

5. 0.39 cm3

6. 3.3 X 1022 atoms

7. a. 5.98 X 10-8 e. 3.4 X 102

b. 3.26 X 10"5 f. 50c. 2.5 X 1017 g. 9 X 10~12

d. 5 X 1048 h. 3.9 X 105

8. a. infinite, definedb. 3c. infinite, definedd. 3e. infinite, definedf. 2g- 3h. infinite number, 22/7 is an infinite decimal

9. a. 5.4 g/cm3 d. 5.3 kg/m3b. 57 g e. 1.1 X 102 cm3

c. 5.5 X 102 cm3

10. a. 5.22

b. 3

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aHfi-pren 3C. 5.6 i. 62d. 1.20 X 102 g. 3.1 X 103e. 3.1 h. 5.000

11. AH except 63,119.56, 61.53, and 3081 are in scien¬tific notation. 63 = 6.3 x 101119.56 is 1.2 X 102.

61,53 is 6.2 X 101.

3.81 is 3.1 X 103.

Challenge, page 931. 34.6 The average should reduce uncertainty.

2. 9 times; about 1013 km out in space

3. 4.2 x 108 cm3

4. 1.0 X 106 cm3

CHAPTER 4 The Mole

¦ ObjectivesWhen students have completed the chapter, they

will be able to:

1. State the meaning of relative atomic mass andidentify the standard for comparison.

2. Calculate the relative mass of several objectswhen given their actual mass and a relative massfor one of the objects.

3. State the number of particles in one mole.4. Find the mass of one mole of a substance when

given the formula for an element or compound.5. Use the definition of a mole to obtain unit factors

relating the mass of an element or compound tothe number of particles present, or to the numberof moles.

6. Convert the amount given to grams, moles, or

molecules when given the formula and amount ofa substance.

7. Differentiate between the number of atoms in onemolecule of a diatomic element like fluorine (2)and the number of atoms in one mole of a dia¬tomic element (12 X 1024).

8. Find the empirical formula when given data forthe composition of a compound.

9. Differentiate between a molecular formula and anempirical formula.

10. Calculate the percent composition of each ele¬ment in a compound when given the formula ofthe compound and a table of atomic masses.

11. Use the definition of molarity as a unitary rate toobtain unit factors to calculate the mass or num¬ber of moles in a given volume of a solution ofknown concentration.

SOT