Mullis 1

Naming CompoundsBinary Ionic Compounds• Cation (+ charge ) is listed first.• Name of cation is the chemical name.

– For many transition metals, the ion is distinguished by the addition of a roman numeral after the chemical name.

– Find charge of the anion and choose appropriate roman numeral to balance the charge.

• Name of the anion ends in –ide.Examples:• Al2O3 aluminum oxide• CuBr2 copper(II) bromide

Mullis 2

Naming Molecular CompoundsBinary Molecular Compounds• If more than one atom, name the first element with

a numerical prefix.• Name the second element with a numerical prefix

and a suffix –ide.• For prefixes, drop o or a if the element name

begins with a vowel. (Examples are monoxide and pentoxide.)

Examples:• N2O4 dinitrogen tetroxide

• OF2 oxygen difluoride

Mullis 3

Numerical PrefixesNumber Prefix

1 mono-

2 di-

3 tri-

4 tetra-

5 penta-

6 hexa-

7 hepta-

8 octa-

9 nona-

10 deca-

Mullis 4

Polyatomic ions• Poly = many• Atomic = atoms• Entire group of atoms is an ion with a

positive or negative charge.• Within the polyatomic ion, atoms are

bound covalently.• Examples:

Sulfate ionSO4

2-

S

Carbonate ionCO3 2-

C

Mullis 5

Chemical Equations•Law of conservation of mass: Atoms are neither created nor destroyed (in ordinary chemical reactions).

–number of atoms on left = number of atoms on right

•The correct formula must be shown for all reactants and products.

–Use oxidation states and ionic charges to correctly write a formula–In balancing, do not split up molecules or change the formula. –Remember common polyatomic ions and diatomic molecules.

Mullis 6

Symbols used in Equations

Yields

Reversible reaction

Reactants are heated

Catalyst added

(s) solid state or precipitate

(l) liquid state

(g) gaseous state

(aq) aqueous state, or dissolved in water

heator

catalyst

Mullis 7

Order for Balancing• MINOH method (Me know chemistry, said

Tarzan as he climbed the stoichiome-tree.)

M - metals Balance metals first.I - ions Balance polyatomic ions.N – nonmetals Balance Cl, S,N.O – oxygen *H – hydrogen

*An odd # on one side and even on other will require you to multiply the odd side to make it even!

Mullis 8

Steps to balance a chemical equation1. Write the formulas and symbols.Cu(s) + Ag(NO3)(aq) Ag(s) + Cu(NO3)2 (aq) 2. Count the atoms on each side of the arrow.

1 Cu 1 Cu 1 Ag 1 Ag 1 N 2 N 3 O 6 O

3. Balance by using coefficients. Do not change subscripts!

Cu(s) + 2Ag(NO3)(aq) 2Ag(s) + Cu(NO3)2 (aq) 4. Check work by counting each element.

1 Cu 1 Cu 2 Ag 2Ag 2 N 2 N 6 O 6 O

Mullis 9

Two Important Principles

1. Every chemical compound has a formula that cannot be altered.

2. A chemical reaction must account for every atom used. (Law of Conservation of Matter)

Mullis 10

Synthesis reactions(composition reactions)

A + B AB

1. Reactions with O2 or S8

Oxides or sulfides formed

16Rb + S8 8Rb2S 2Mg + O2 2MgO

2. Metals with halogensa. Ionic compounds formedb. Examples are NaF and NaCl

Mullis 11

Synthesis reactions, cont.A + B AB

3. Two compounds combine to form a single product.

N2O3 + H2O 2HNO2

4. Oxides with watera. With metal: Metal hydroxides produced

CaO + H2O Ca(OH)2

b. With nonmetal: Oxyacids produced

SO3 + H2O H2SO4

Mullis 12

Synthesis reactions, cont.A + B AB

5. Metal oxides with CO2

5. Carbonates produced

6. CaO + CO2 CaCO3

6. Metal oxides with SO2

Sulfites produced

CaO + SO2 CaSO3

Mullis 13

Decomposition reactions

AB A + B1. Binary compounds split up

a. Electrolysis is decomposition by electric current

Example: H2O 2H2 + O2

b. Electrolysis is decomposition by electric current

2. Metals with carbonatesa. Metal oxide and carbon dioxide are formed

b. Example: CaCO3 CaO + CO2

3. Metal hydroxidesa. When heated, metal hydroxides decompose to metal oxide and

water.

b. Example: Ca(OH)2 CaO + H2O

electricity

Mullis 14

Decomposition reactions

AB A + B

4. Metal chloratesa. When heated, metal chlorates decompose to

metal chloride and oxygen.

b. Example: 2KClO3 2KCl + 3O2

5. Decomposition of acidsa. Some acids decompose into nonmetal oxides

and water.

b. Example: H2CO3 CO2 + H2O

Mullis 15

Single Replacement Reactions

C + AB A + CB1. Metal replaces another metal

Replacing metal must be the more active metal!

Example: 2Al + 3Pb(NO3)2 3Pb + 2Al(NO3)3

2. Metal replaces H in water

a. Active metals produce metal hydroxide and waterb. Less reactive metals make metal oxide and hydrogen gas

Examples: 2Na + 2H2O 2NaOH + H2

3Fe + 4H2O Fe3O4 + 4H2

Mullis 16

Single Replacement Reactions

C + AB A + CB3. Metal replaces H in an acid

More active metals involved

Example: Mg + 2HCl H2 + MgCl2

4. Halogen replaces another halogenFluorine is most reactive and replaces others.

Example: Cl2 + 2KBr 2KCl + Br2

Br2 + 2KCl No reaction

Mullis 17

Double Replacement Reactions

AB + CD AD + CB

1. Precipitate forms (a salt) .

Example: 2KI(aq) + Pb(NO3)2(aq) PbI2(s) + 2KNO3(aq)

2. Gas forms.

FeS(s) + 2HCl(aq) H2S (g) + 2FeCl2(aq)

3. Water forms.

NaOH(aq) + HCl(aq) NaCl (aq) + H2O (l)

Mullis 18

Combustion ReactionsCH4 + 2O2 2H2O + CO2

• One of the reactants is oxygen.• In this class, all or our combustion reactions will

be oxygen and hydrocarbons. • The products of this type of combustion reaction

will always be water and carbon dioxide.• To quickly balance combustion reactions, START

WITH WATER and multiply it by an EVEN coefficient.

Mullis 19

Practice: Balancing equations

1. Solid sodium combines with chlorine gas to produce solid sodium chloride.

2. When solid copper reacts with aqueous silver nitrate, the products are aqueous copper(II) nitrate and solid silver.

3. In a blast furnace, the reaction between solid iron(III) oxide and carbon monoxide gas produces solid iron and carbon dioxide gas.

Mullis 20

Practice: Balancing equations

1. Solid sodium combines with chlorine gas to produce solid sodium chloride.

2. When solid copper reacts with aqueous silver nitrate, the products are aqueous copper(II) nitrate and solid silver.

3. In a blast furnace, the reaction between solid iron(III) oxide and carbon monoxide gas produces solid iron and carbon dioxide gas.

Mullis 21

Reaction types: Summary

Synthesis Reactant ProductOxygen Oxide Halogen Halide

H2O + nonmetal oxide AcidH2O + metal oxide Base (R-OH)

DecompositionReactant ProductBinary comp. ElementsMetal CO3 Metal oxide & CO2

Metal OH Metal oxide & H2O

Metal ClO3 Metal chloride & O2

Acids Nonmetal oxide & H2O

Mullis 22

Reaction types: Summary, cont.Single replacementSingle and a couple Couple and a single

1. Metal replaces metal in compound2. Metal replaces H in water H2(g) product

3. Metal replaces H in acid H2(g) product

4. Halogen replaces another

Double replacement2 couples 2 different couples

1. Precipitate forms (s) product2. Gas forms (g) product3. Water forms H2O product