Bonding and Inorganic Nomenclature

transcript

Bonding andInorganic Nomenclature

Chemistry

NaClO3

Fe(ClO3)2

lithium nitrate

lithium nitride

lithium nitrite

lead (II) sulfide

barium sulfide

sulfur dioxide

Fe(ClO3)3

Inorganic Nomenclature

potassiumnitrateKNO3

sodiumhydroxide

dinitrogen monoxideN2O

copper (II)sulfate

Cu2SO4

Vocabulary

• Chemical Bond

– attractive force between atoms or ions that binds them together as a unit

– bonds form in order to…• decrease potential energy (PE)

• increase stability

Courtesy Christy Johannesson www.nisd.net/communicationsarts/pages/chem

Covalent Bonding - True Molecules

Types of Bonds

Diatomic Molecule

Ammonia

Nitrogen

In insulators (like wood),the v.e– are attachedto particular atoms.

Metallic Bonds

In metals, valence shells of atoms overlap, so v.e– are free to travel between atoms through material.

Not so in metals.

All due to free-moving

v.e–.

Properties of Metals

ductile conduct heat and electricity

malleable

Ionic Bonding - Crystal Lattice

Types of Bonds

Table salt

Properties of Salts

1. very hard –

2. high melting points –

3. brittle –

each ion is bondedto several oppositely-charged ions

many bonds must be broken

with sufficient force,like atoms arebrought next toeach other and repel

calcite

Chemical Bonding

Ionic Bonds: atoms give up or gain e– and are attracted to each other by coulombic (electrical) attraction

Na Na1+ Cl Cl1–loses e– gains e–

Na1+ + Cl1– NaCl

K1+ + NO31– KNO3

ionic compounds = salts

where NO31– is a polyatomic ion:

a charged group of atoms that stay together

Writing Formulas of Ionic Compounds

chemical formula:

To write an ionic compound’s formula, we need:

1. the two types of ions

2. the charge on each ion

Na1+ and F1–

Ba2+ and O2–

Na1+ and O2–

Ba2+ and F1–

shows types of atomsand how many of each

(i.e., “pink” and “blue”)

has neutral charge;

charge on cation / anion“becomes” subscript of anion / cation

** Warning:

Al3+ and O2– Ba2+ and S2– In3+ and Br1–

Reduce to lowest terms.

Al O Ba S In Br 2 3 2 2 31

Al2O3 BaS InBr3

criss-cross rule:

Writing Formulas w/Polyatomic Ions

Parentheses are required only when you need morethan one “bunch” of a particular polyatomic ion.

Ba2+ and SO42–

Mg2+ and NO21–

NH41+ and ClO3

Sn4+ and SO42–

Fe3+ and Cr2O72–

NH41+ and N3–

Mg(NO2)2

NH4ClO3

Sn(SO4)2

Fe2(Cr2O7)3

(NH4)3N

A. To name, given the formula:

2. Use name of anion (it has the ending “ide”).

1. Use name of cation.

sodium fluoride

barium oxide

sodium oxide

barium fluoride

1. Write symbols for the two types of ions.

2. Balance charges to write formula.

silver sulfide

zinc phosphide

calcium iodide

B. To write formula, given the name:

Ag1+ S2– Ag2S

Zn2+ P3– Zn3P2

I1– Ca2+ CaI2

Ionic Compounds (cation/anion combos)

The Unique-Charge Cations (Always have the same charge when ionized)

The unique-charge cations are:

groups 1, 2, 13, and Ag1+, Cd2+, and Zn2+ 1

Variable-Charge Cations with Elemental Anions

The Variable (multiple)-charge cations are:

Pb, Sn, and the transition elements

(but – not Ag+1, Cd+2, or Zn+2)

iron oxide

A. To name variable charge elements, given the formula:

1.Figure out charge on cation.2. Write name of cation.

3. Write Roman numerals in ( ) to show cation’s charge.

4. Write name of anion.

iron oxide

Stock Systemof nomenclature

Fe? O2– iron (II) oxide

Fe? O2– iron (III) oxide

copper bromide

Cu? Br1– copper (I) bromide

Cu2+ Br1– copper (II) bromide

Br1–

O2– O2–

Fe3+ Fe3+

B. To find the formula, given the name:

1. Write symbols for the two types of ions.

2. Balance charges to write formula.

cobalt (III) chloride

tin (IV) oxide

tin (II) oxide

Co3+ Cl1– CoCl3

Compounds Containing Polyatomic Ions

Insert name of ionwhere it should goin the compound’sname.

Write formulas:

iron (III) nitrite

ammonium phosphide

ammonium chlorate

zinc phosphate

lead (II) permanganate

iron (III) nitrite

ammonium phosphide

ammonium chlorate

zinc phosphate

lead (II) permanganate

Fe3+ NO31– Fe(NO3)3

P3– (NH4)3P

ClO31– NH4ClO3

Zn2+ PO43– Zn3(PO4)2

Pb2+ MnO41– Pb(MnO4)2

Write names:

(NH4)2S2O3

AgBrO3

(NH4)3N

U(CrO4)3

Cr2(SO3)3

(NH4)2S2O3

AgBrO3

(NH4)3N

U(CrO4)3

Cr2(SO3)3

ammonium thiosulfate

silver bromate

ammonium nitride

U? CrO42–

CrO42–

uranium (VI) chromate

Cr? Cr?

Cr3+ Cr3+ SO3

2– SO32–

SO32– chromium (III) sulfite

Binary Molecular Compounds(Covalent Compounds)

Nonmetal + Nonmetal

Covalent Bonds

…atoms share e– to get a full valence shell

Lewis structure:

1. Two shared e– make a single covalent bond,four make a double bond, etc.

2. unshared pairs: pairs of unbonded valence e–

3. Each atom needs a full outer shell, i.e., 8 e–.

Exception: H needs 2 e–

a model of a covalent molecule that

shows all of the valence e–

Group 14 (4 v.e–)

Group 17 (7 v.e–)

both need 8 v.e– for a full outer shell (octet rule)

x xF x

carbon tetrafluoride (CF4)

x xF x

methane (CH4)

o oH x

nitrogen triiodide (NI3)

carbon dioxide (CO2)

x x I x

x x I xoo

o o O = C = O

x x x x

butter

(consist of twononmetal elements)

covalent compounds = molecular compounds

-- have lower melting points than do ionic compounds

Covalent Compounds -- contain two types of

** Key:

Use Greek prefixes to indicate howmany atoms of each element, butdon’t use “mono” on first element.

nonmetals nonmetals

FORGET CHARGES!

What to do:

1 –2 –

6 –7 –

10 –

EXAMPLES:

carbon dioxide

dinitrogen trioxide

carbon tetrachloride

carbon monoxide

dinitrogen pentoxide

nitrogen triiodide

Binary Compounds Containing Two Nonmetals

To name these compounds, give the name of the less electronegative element first with the Greek prefix indicating the number of atoms of that element present, followed by the name of the more electronegative non-metal with the Greek prefix indicating the number of atoms of that element present and with its ending replaced by the suffix –ide.

Prefixes you should know:

Mono Di Tri Tetra Penta Hexa Hepta Octa Nona Deca

1 2 3 4 5 6 7 8 9 10

Dihydrogen Monoxide:A Tale of Danger and

Irresponsibility

-- major component of acid rain

-- found in all cancer cells

-- inhalation can be deadly

-- excessive ingestion results in acute physical symptoms:

e.g., frequent urination, bloated sensation, profuse sweating

-- often an industrial byproduct of chemical reactions; dumped wholesale into rivers and lakes

Binary CompoundsContaining Two Nonmetals (Type III Compounds)

1. ________________ diarsenic trisulfide

2. ________________ sulfur dioxide

3. P2O5 ____________________

4. ________________ carbon dioxide

5. N2O5 ____________________

6. H2O ____________________

diphosphorus pentoxide

dinitrogen pentoxide

dihydrogen monoxide

Binary Molecular Compounds

N2O dinitrogen monoxideN2O3 dinitrogen trioxideN2O5 dinitrogen pentoxide

ICl iodine monochlorideICl3 iodine trichloride

SO2 sulfur dioxideSO3 sulfur trioxide

Naming Binary CompoundsBinary Compound?

Metal Present?

Does the metal formmore than one cation?

Type IIIUse Greek

Prefixes

Type IUse the elementname for the cation.

Type IIDetermine the charge of the cation; use a Romannumeral after the cationname.

Zumdahl, Zumdahl, DeCoste, World of Chemistry 2002, page 98

Naming Simple Chemical Compounds

Ionic (metal and nonmetal) Covalent (2 nonmetals)

Formsonly onepositive

Formsmore than

one positiveion

Nonmetal

Use the name of element

Use elementname followed

by a Romannumeral to

show the charge

Firstnonmetal

Secondnonmetal

Beforeelement name

use a prefixto matchsubscript

Use a prefixbefore

element name and end with ide

SingleNegative

Polyatomic Ion

Use the nameof the

element, butend with ide

Use thename of

polyatomicion (ate or

Prefixes – Binary Molecular CompoundsGreek Prefixes for Two Nonmetals

Number Indicated Prefixes

1 mono- 2 di- 3 tri- 4 tetra- 5 penta- 6 hexa- 7 hepta- 8 octa- 9 nona-10 deca-

in text

phosphate

sulfate

carbonate

chlorate

nitrate

Polyatomic Ions - Memorize

phosphATE

sulfATE

carbonATE

chlorATE

nitrATE

PO43- ……………

SO42- ……………

CO32- …………..

ClO31- …………..

NO31- ………..….

Eight “-ATE’s”

Exceptions:

ammonium

hydroxide

cyanide

NH41+ ……………

OH1- ……………

CN1- …………..

Pattern to Memorizing Nomenclature

XY“-ide”

XYO3“-ate”

XYO2“-ite”

XYO“hypo___-ite”

XYO4“per___-ate”

normal 1 less oxygen 2 less oxygen1 more oxygen

Polyatomic Ion: a group of atoms that stay together and have a single, overall charge.

BrO41-

Perbromate ion

BrO31-

Bromate ion

BrO21-

Bromite ion

Hypobromite ion

CO42- CO3

Carbonate ion

CO22- CO2-

ClO41- ClO3

Chlorate ion

ClO21- ClO1-

IO41- IO3

Iodate ion

IO21- IO1-

NO41- NO3

Nitrate ion

NO21- NO1-

PO53- PO4

Phosphate ion

PO33- PO2

SO52- SO4

Sulfate ion

SO32- SO2

1 more oxygen “normal” 1 less oxygen 2 less oxygen

Common Polyatomic Ions(pg 123 in text)

Names of Common Polyatomic Ions

Ion Name Ion Name

NH4 1+ ammonium CO3 2- carbonate

NO2 1- nitrite HCO3 1- hydrogen carbonate NO3 1- nitrate (“bicarbonate” is a widely SO3 2- sulfite used common name) SO4 2- sulfate ClO 1- hypochlorite HSO4 1- hydrogen sulfate ClO2 1- chlorite

(“bisulfate” is a widely ClO3 1- chlorate used common name) ClO4 1- perchlorate OH 1- hydroxide C2H3O2 2- acetate CN 1- cyanide MnO4 1- permanganate PO4 3- phosphate Cr2O7 2- dichromate HPO4 2- hydrogen phosphate CrO4 2- chromate H2PO4 1- dihydrogen phosphate O2 2- peroxide

Zumdahl, Zumdahl, DeCoste, World of Chemistry 2002, page 100 Print Version

Binary Hydrogen Compoundsof Nonmetals When Dissolved in Water

(These compounds are commonly called acids.)

The prefix hydro- is used to represent hydrogen, followed by the nameof the nonmetal with its ending replaced by the suffix –ic and the wordacid added. (See page 133 in text for common acids)

Examples:

*The name of this compound would be hydrogen chloride if it was NOT dissolved in water.

Hydrochloric acid

Hydrobromic acid

Common Acids (pg 133 in text)

• Hydrochloric HCL

• Sulfuric H2SO4

• Nitric HNO3

• Acetic HC2H3O2

• Phosphoric H3PO4

• Carbonic H2CO3

• Hydrofluoric HF

Empirical Formula and Molecular Formula

CompoundMolecular Formula

EmpiricalFormula

glucose C6H12O6

propane C3H8

butane C4H10

naphthalene C10H8

sucrose C12H22O11

octane C8H18

lowest-termsformula

shows the true numberand type of atoms in a

m’cule

C12H22O11

Traditional System of Nomenclature

…used historically (and still some today) to name compounds w/multiple-charge cations

To use: 1. Use Latin root of cation.

2. Use -ic ending for higher charge; -ous ending for lower charge.

3. Then say name of anion, as usual.

Element Latin root -ic -ous

gold, Au aur- Au3+

lead, Pb plumb- Pb4+

tin, Sn stann- Sn4+

copper, Cu cupr- Cu2+

iron, Fe ferr- Fe3+

Write formulas: cuprous sulfide

auric nitrite

ferrous fluoride

Write names: Pb3P4

Sn(OH)4

Cu1+ S2– Cu2S

Au3+ NO21– Au(NO2)3

Fe2+ F1– FeF2

cuprous sulfide

auric nitrite

ferrous fluoride

Sn(OH)4

Pb? P3– Pb? Pb?

Pb? Pb? Pb?

P3– P3– P3–

P3– P3– Pb2+

Pb4+ Pb4+

plumbic phosphidePb2+

plumbous phosphide

OH1– Sn4+ Sn? OH1– OH1–

OH1–

stannic hydroxide

In insulators (like wood),the v.e– are attachedto particular atoms.

Metallic Bonds

In metals, valence shells of atoms overlap, so v.e– are free to travel between atoms through material.

Not so in metals.

All due to free-moving

v.e–.

Properties of Metals

ductile conduct heat and electricity

malleable

Bonding and Inorganic Nomenclature

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