Chemistry: Reactions, Equations, and Stoichiometry Key Concepts

reactants

substances present before a chemical reaction occurs

products

substances formed during a chemical reaction

What does (aq) mean in a chemical equation?

aqueous (dissolved in water)

What law is followed when balancing equations?

law of conservation of mass

What can be changed when balancing equations?

Coefficients only

Why must equations be balanced?

Matter cannot be created or destroyed.

How many particles are in 1 mole?

6.02x10^23

What volume does 1 mole of gas occupy at STP?

22.4 L

theoretical yield

The maximum amount of product that can be produced from a given amount of reactant

actual yield

The amount of product actually produced.

percent yield

actual yield/theoretical yield x 100

molarity

The concentration of a solution in moles per liter.

formula for molarity

moles of solute/liters of solution

Metal Carbonate Rule

Metal Oxide + Carbon dioxide

Metal Hydroxide Rule

Metal Oxide + Water

Metal Chlorate Rule

Metal Chloride + Oxygen gas

synthesis formula

A + B → AB

decomposition formula

AB → A + B

single replacement formula

A+BC → B+AC

double replacement formula

AB + CD → AD + CB

What indicates that a double replacement reaction occurred?

Formation of a precipitate, gas, or water.

combustion formula

CxHy + O2 → CO2 + H2O

oxidation

loss of electrons

reduction

gain of electrons

OIL RIG

Oxidation is loss, reduction is gain

oxidizing agent

The substance that causes oxidation and is reduced.

reducing agent

The substance that causes reduction and is oxidized.

complete ionic equation

An equation that shows dissolved ionic compounds as dissociated free ions

net ionic equation

An equation showing only the particles involved in the reaction.

spectator ions

ions that do not participate in a reaction