balance the following equations:

(a) C₂H₆ + O₂ --> CO₂ + H₂O

(b) PCl₅ + H₂O --> H₃PO₄ + HCl

(c) Fe₂(SO₄)₃ + NH₃ + H₂O --> Fe(OH)₃ + (NH₄)₂SO₄

(a) 2C₂H₆ + 7O₂ --> 4CO₂ + 6H₂O

(b) PCl₅ + 4H₂O --> H₃PO₄ + 5HCl

(c) Fe₂(SO₄)₃ + 6NH₃ + 6H₂O --> 2Fe(OH)₃ + 3(NH₄)₂SO₄

balance the following equations:

(a) KNO₃ --> KNO₂ + O₂

(b) NH₄NO₃ --> N₂O + H₂O

(c) HCl + CaCO₃ --> CaCl₂ + H₂O + CO₂

(a) 2KNO₃ --> 2KNO₂ + O₂

(b) NH₄NO₃ --> N₂O + 2H₂O

(c) 2HCl + CaCO₃ --> CaCl₂ + H₂O + CO₂

100% dissociated into ions. This is an electrolyte that exists in solution almost entirely as ions

NaCl_(s) --H₂O--> Na⁺_(aq) Cl^-_(aq) 

All soluble ionic compounds are strong electrolytes

is partially dissolved into ions. This is an electrolyte that disolves in water to give a relatively small percentage of ions. There is an equalibrium between the dissociated and non-dissociated species

CH₃CO₂H_(aq) ↔ CH₃CO₂^-_(aq) + H⁺_(aq)

does not conduct electricity as there are no ions present. Solutions of molecular compounds such as sugars and alcohols do not ionize or dissociate in aqueous solution

C₆H₂O_6(s) --H₂O--> C₆H₁₂O_6(aq)

Ex: sugars and alcohols

a reaction in which the ions of the reactants exchange "partners"

AB + CD = AD + CB

AgNO_3(aq) + NaCl_(aq) --> AgCl_(s) + NaNO_3(aq)

predict whether each of the following ionic compounds is likely to be soluble in water:

(a) LiNO₃

(b) CaCl₂

(c) CuO

(d) NaCH₃CO₂

(a) LiNO₃                 soluble

(b) CaCl₂                 soluble

(c) CuO                insoluble

(d) NaCH₃CO₂         soluble

when 2 ionic compounds in aqueous solution react to form a solid precipitate, they do so by exchanging ions. Predict the products in the following reactions:

(a) AgNO_3(aq) + KCl_(aq) -->

(b) Pb(NO₃)_2(aq) + K₂CrO_4(aq) -->

(c) Pb(NO₃)_2(aq) + (NH₄)₂S_(aq) -->

(d) FeCl_3(aq) + 3NaOH_(aq) -->

(a) AgNO_3(aq) + KCl_(aq) -->

AgCl_(s) + KNO_3(aq)

(b) Pb(NO₃)_2(aq) + K₂CrO_4(aq) -->

PbCrO_4(s) + 2KNO_3(aq)

(c) Pb(NO₃)_2(aq) + (NH₄)₂S_(aq) -->

PbS_(s) + 2NH₄NO_3(aq)

(d) FeCl_3(aq) + 3NaOH_(aq) -->

Fe(OH)_3(s) + 3NaCl_(aq)

a chemical equation in which the reactants and products are written as molecules or whole units

Ba(NO₃)_2(aq) + NaSO_4(aq) --> 2NaNO_3(aq) + BaSO_4(aq)

a chemical equation in which the dissolved species are written as separate ions in aqueous solution

Ba²⁺_(aq) + 2NO₃^-_(aq) + 2Na⁺_(aq) + SO₄^2-_(aq) -->

2Na⁺_(aq) + 2NO₃^-_(aq) + BaSO_4(s)

(Na⁺ and NO₃^- are spectator ions)

an ionic equation from which the spectator ions have been cancelled

Ba²⁺_(aq) + SO₄^2-_(aq) --> BaSO_4(s)

write the net ionic equation for the reaction of silver nitrate with sodium chloride

Ag⁺_(aq) + Cl^-_(aq) -->AgCl_(s)

Fe(NO₃)_2(aq) + 2NaCl_(aq) --> 2NaNO_3(aq) + FeCl_2(aq)

--> no precipitate forms

a sunstance that produces H⁺ ions or H₃O⁺ ions in water

HCl + H₂O --> H₃O⁺ + Cl^-

HCl --H₂O--> H⁺ + Cl^-

a substance that produces OH^- ions in water

NH₃ + H₂O ↔ NH₄⁺ + OH^-

a proton donor

HNO₃ + H₂O --> H₃O⁺ + NO₃^-

must contain at least one ionizable proton!

a proton acceptor

NH₃ + H₂O ↔ NH₄⁺ + OH^-

an acid that ionizes completely in water; it is a strong electrolyte

Ex: HCl_(aq) --> H⁺_(aq) + Cl^-_(aq)

strong acids: HCl, HBr, HI, HNO₃, HClO₄, H₂SO₄

an acid that only partly ionizes in water; it is a weak electrolyte

Ex: CH₃CO₂H_(aq) ↔ H⁺_(aq) + CH₃CO₂^-_(aq)

some weak acids: HF, HNO₂, CH₃CO₂H, HCN, H₃PO₄

what is a strong base?

a base that ionizes completely in water; it is a strong electrolyte

NaOH_(s) --> Na⁺_(aq) + OH^-_(aq)

Strong bases: LiOH, NaOH, KOH, Ba(OH)₂, group I and II hydroxide

a base that only partly ionizes in water; it is a weak electrolyte

NH_3(aq) + H₂O_(l) ↔ NH₄⁺_(aq) + OH^-_(aq)

Ex: ammonia

a reaction between an acid and a base that results in an ionic compound (salt) and possibly water

Acid + Base --> Salt + Water

HCl_(aq) + NaOH_(aq) --> NaCl_(aq) + H₂O_(l)

H⁺_(aq) + Cl^-_(aq) + Na⁺_(aq) + OH^-_(aq) --> Na⁺_{(aq) +}Cl^-_(aq) + H₂O_(l)

H⁺_(aq) + OH^-_(aq) -->H₂O_(l)

HCN_(aq) + KOH_(aq) --> KCN_(aq) + H₂O_(l)

HCN_(aq) + K⁺_(aq) + OH^-_(aq) --> K^+_(aq) + CN^-_(aq) + H₂O_(l)

HCN_(aq) + OH^-_(aq) --> CN^-_(aq) + H₂O_(l)

oxides of non-metals are called acidic oxides (form acids with water)

CO_2(g) + H₂O_(l) --> H₂CO_3(aq)

oxides of metals (form bases with water)

BaO_(s) + H₂O_(l) --> Ba(OH)_2(aq)

(corbonates, CO₃^2-, sulfites, SO₃^2-, sulfides, S^2-)

react with acids to form a gaseous product

CO_2(g)

H₂S_(g)

SO_2(g)

NH_3(g)

NiCO_3(s) + H₂SO_4(aq) --> NiSO_4(aq) + H₂CO_3(aq)

--> NiSO_4(aq) + H₂O_(l) + CO_2(aq)

NH₄⁺ SO₄^2-

(NH₄)₂SO_4(aq) + 2NaOH_(aq) --> 2NH_3(g) + Na₂SO_4(aq) + 2H₂O_(l)

Fe_(s) + CuSO_4(aq) --> FeSO_4(aq) + Cu_(s)

Fe_(s) + Cu²⁺_(aq) + SO₄^2-_(aq) --> Fe²⁺_(aq) + SO₄^2-_(aq) + Cu_(s)

Fe_(s) + Cu²⁺_(aq) --> Fe²⁺_(aq) + Cu_(s)

Fe_(s) --> Fe²⁺_(aq) + 2e^-

Fe is oxidized

Cu²⁺_(aq) + 2e^- --> Cu_(s)

Cu²⁺ is reduced

loss of electron (gain in oxidation #)

Oxidation

Is         

Loss      

gain of electron (decrease in ocidation #)

Reduction

Is          

Gain       

zinc metal reacts with copper (II) sulfate to form copper metal. What is the reducing agent in the reaction?

Zn_(s) + CuSO_4(aq) --> ZnSO_4(aq) + Cu_(s)

Zn_(s) + Cu²⁺_(aq) --> Zn²⁺_(aq) + Cu_(s)

Zn is the reducing agent

copper wire reacts with silver nitrate to form silver metal. what is the oxidizing agent in the reaction?

Cu_(s) + 2AgNO_3(aq) --> Cu(NO₃)_2(aq) 2Ag_(s)

Cu_(s) + Ag⁺_(aq) --> Cu²⁺_(aq) + Ag_(s)

Ag⁺ is the oxidizing agent

(oxidation)

free elements (uncombined state) have an oxidation number of zero. they are what?

(oxidation)

in monatomic ions, the oxidation number is equal to the charge on the ion. what are they?

Li⁺, Li = +1

Fe³⁺, Fe = +3

O^2-, O = -2

(oxidation)

the oxidation number of oxygen is usually -2. In H₂O₂ and O₂^2- it is what?

(a) Group IA metals are what charge?

(b) Group IIA metals are what charge?

(c) Fluorine is always what charge?

(a) +1

(b) +2

(c) -1

H = +1

C = +4

O = -2

(+1 X 1) + x + (-2 X 3) = -1

                    1 + x - 6 = -1

                          x - 5 = -1

                               x = +4

Na = +1

I = +5

O = -2

(+1 X 1) + x + (-2 X 3) = 0

                                 x = +5

I = +7

F = -1

x + (-1 X 7) = 0

                  x = +7

K = +1

Cr = +6

O = -2

(+1 X 2) + 2x + (-2 X 7) = 0

                               2x = +12

                                 x = 6