Chemistry Ch.7 - Key Concepts

Rules for Writing Chemical Equations

1. Always specify what state the chemical equation is in

2. Always must obey the Law of Conservation (each atom must be balanced)

3. Reactants on left, products on right

4. Never change subscripts on atoms

Tips for Balancing Chemical Equations

1. Balance any element that appears more than once on either side LAST

2. Treat polyatomic ions that appear on both sides as a single unit to balance

Total Ionic Equation

Shows the species as they actually are in solution by listing all dissolved (aq) ionic compounds and strong acids as separated, individual ions

Net Ionic Equations

Simplifies the total ionic equation by removing spectator ions and leaving only the actively involved species in the solution.

Spectator Ion

An ion or atom that has experienced no change

• Same on both sides

Solubility Rules

1. All [Perchlorate, nitrate, nitride, and acetate] salts are soluble

2. All [G1 metal and ammonium (NH4 +)] salts are soluble

3. All [chloride, bromide, and iodine] salts are soluble

4. All [sulfate salts] are soluble EXCEPT -[Chloride, bromide, Lead (II), Mercury (I), calcium, strontium, and barium].

5. All other anions will form insoluble salts UNLESS the cation is a G1 METAL or AMMONIUM

Precipitation Reactions

Soluble and insoluble salts

• Dissolve in water = soluble

• Not dissoluble = insoluble salts

Arrhenius Acid-Base Theory

Produces OH- ions in an aqueous solution

• Not all compounds containing an OH group are considered an Arrhenius base

• —> ex: OH3OH is not soluble

Arrhenius Acid

Produces H+ ions in an aqueous solution

• H+ are highly reactive

• In water, H+ ions always associate with H2O molecules

• EX: HCl Ions → H3O+

Bronsted-Lowly Acid-Base Theory: Acid

A proton (H+) donor

• Donates H+ to water

Bronsted-Lowly Acid-Base Theory: Base

A proton (H+) receiver

Decomposition Reaction

One reactant and multiple products.

Combination (synthesis)

Multiple reactants and one product.

exchange (double replacement)

The ions of two ionic compounds "swap partners."

Displacement (single replacement)

Uneven exchange of ions

What product is formed when acid reacts with a hydroxide base?

water (l) and a salt (aq)

What product is formed when Acids react with carbonate?

carbon dioxide, salt, and water.