C H E M I S T R Y

Chapter 4Chapter 4Reactions in Aqueous SolutionReactions in Aqueous Solution

Naming Chemical Naming Chemical CompoundsCompounds

Binary Acids

Hydrogen + nonmetal (no oxygen)

Naming: Hydro+root of lement+ic acid ending

HCl hydrochloric acid

HBr hydrobromic acid

HF hydrofluoric acid

*Exception: HCN – hydrocyanic acid

Naming Chemical Naming Chemical CompoundsCompounds

“ate”“ic”

“ite”“ous”

Polyatomic anion No hydro- prefixRoot of polyatomic anion + ous acid endingOr ic acid ending

ExamplesExamplesName the following acids

A.H2S

B.H2CO3

C.HBrO3

D.H3PO3

Some Ways That Chemical Some Ways That Chemical Reactions OccurReactions Occur

Precipitation Reactions: Processes in which soluble reactants yield an insoluble solid product that falls out of solution.

NaNO3(aq) + AgCl(s)AgNO3(aq) + NaCl(aq)

Some Ways That Chemical Some Ways That Chemical Reactions OccurReactions Occur

Acid-Base Neutralization Reactions: Processes in which an acid reacts with a base to yield water plus a salt.

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

Acid + Base Water + Salt

Some Ways That Chemical Some Ways That Chemical Reactions OccurReactions Occur

Oxidation-Reduction (Redox) Reactions: Processes in which one or more electrons are transferred between reaction partners (atoms, molecules, or ions).

MgCl2(aq) + H2(g)Mg(s) + 2HCl(aq)

Element + Compound Compound + Element

Neutral state: (s), (l), (g)

ElectrolytesElectrolytes

Electrolytes in Aqueous Electrolytes in Aqueous SolutionSolution

Weak Electrolytes: Compounds that dissociate to a small extent into ions when dissolved in water.

H1+(aq) + CH3CO21-(aq)CH3CO2H(aq)

Strong Electrolytes: Compounds that dissociate to a large extent into ions when dissolved in water.

K1+(aq) + Cl1-(aq)KCl(aq)

Nonelectrolytes: Substances which do not produce ions in aqueous solutions.

H2OC12H22O11(aq)C12H22O11(s)

Electrolytes in Aqueous Electrolytes in Aqueous SolutionSolution

Strong Acids: hydrochloric acid, hydrobromic acid, hydroiodic acid, perchloric acid, nitric acid, sulfuric acid.

Memorize these acids

Electrolytes in Aqueous Electrolytes in Aqueous SolutionSolution

Ionic Compounds

Electrolytes in Aqueous Electrolytes in Aqueous SolutionSolution

Weak acids

Electrolytes in Aqueous Electrolytes in Aqueous SolutionSolution

Molecular Compounds(other than any strong or weak electrolytes)

Aqueous Reactions and Net Aqueous Reactions and Net Ionic EquationsIonic Equations

Molecular Equation: All substances in the chemical equation are written using their complete formulas as if they were molecules.

strong electrolytesindicated as (aq)soluble

Precipitateinsoluble

NaNO3(aq) + AgCl(s)AgNO3(aq) + NaCl(aq)

Aqueous Reactions and Net Aqueous Reactions and Net Ionic EquationsIonic Equations

Ionic Equation: All of the strong electrolytes are written as ions.

Na1+(aq) + NO31- (aq) + AgCl(s)

NaNO3(aq)

AgNO3(aq) NaCl(aq)

Ag2+(aq) + NO31- (aq) + Na1+(aq) + Cl1-(aq)

Aqueous Reactions and Net Aqueous Reactions and Net Ionic EquationsIonic Equations

Spectator Ions: Ions that undergo no change during the reaction and appear on both sides of the reaction arrow.

Na1+(aq) + NO31- (aq) + AgCl(s)

Ag2+(aq) + NO31- (aq) + Na1+(aq) + Cl1-(aq)

Aqueous Reactions and Net Aqueous Reactions and Net Ionic EquationsIonic Equations

AgCl2(s)Ag+(aq) + Cl1-(aq)

Net Ionic Equation: Only the ions undergoing change are shown.

Precipitation Reactions and Precipitation Reactions and Solubility GuidelinesSolubility Guidelines

Precipitation Reactions and Precipitation Reactions and Solubility GuidelinesSolubility Guidelines

Write the chemical formulas of the products (use proper ionic rules).

CB + ADAB + CD

double replacement reaction

*Remember that metal cation does not bond to another metal cation

Precipitation Reactions and Precipitation Reactions and Solubility GuidelinesSolubility Guidelines

Write the molecular, ionic, and net ionic equations for the reaction that occurs when aqueous solutions of Iron(III) nitrate and Sodium Hydroxide are mixed.

ExampleExample Write the molecular, ionic, and net ionic

equations for the reaction that occurs when aqueous solutions of PbCl2 and Na2SO4 are mixed

Aqueous solution of Mg(NO3)2 and NH4OH

Acids, Bases, and Neutralization Acids, Bases, and Neutralization ReactionsReactions

H3O1+(aq) + Cl1-(aq)HCl(aq) + H2O(aq)

Acid (Arrhenius): A substance that dissociates in water to produce hydrogen ions, H1+:

H1+(aq) + A1-(aq)HA(aq)

In water, acids produce hydronium ions, H3O1+:

H1+(aq) + Cl1-(aq)HCl(aq)

Acids, Bases, and Neutralization Acids, Bases, and Neutralization ReactionsReactions

Ammonia, commonly called “ammonium hydroxide” is a base:

M1+(aq) + OH1-(aq)MOH(aq)

Na1+(aq) + OH1-(aq)NaOH(aq)

NH41+(aq) + OH1-(aq)NH3(aq) + H2O(aq)

Base (Arrhenius): A substance that dissociates in water to produce hydroxide ions, OH1-:

Acids, Bases, and Neutralization Acids, Bases, and Neutralization ReactionsReactions

Weak acids and weak bases are weak electrolytes.

Strong acids and strong bases are strong electrolytes.

Acids, Bases, and Acids, Bases, and Neutralization ReactionsNeutralization Reactions

MA + H2OHA + MOH

These acid-base neutralization reactions are double-replacement reactions just like the precipitation reactions:

or

MA + HOHHA + MOH

WaterAcid Base Salt

Acids, Bases, and Neutralization Acids, Bases, and Neutralization ReactionsReactions

•Write the molecular, ionic, and net ionic equations for the reaction of aqueous H2SO4 and aqueous KOH

Acids, Bases, and Neutralization Acids, Bases, and Neutralization ReactionsReactions

Write the molecular, ionic, and net ionic equations for the reaction of aqueous NaOH and aqueous HF.

ExamplesExamplesPredict the product and write a

molecular equation, ionic equation and net ionic equation for the following reactions◦K2CO3(aq) + CuCl2(aq)

◦HNO3(aq) + LiOH(aq)

◦H2SO3(aq) + NaOH