AP Chemistry Unit 7 Test

reversible reactions

reactions that can take place in both directions

equilibrium

when the concentrations of the reactants and products stop changing

the rate of the forward reaction = the rate of the reverse reaction

at equilibrium, what is equal?

Keq = [C]ᶜ[D]ᵈ / [A]ᵃ[B]ᵇ

(equilibrium concentrations)

equilibrium constant

favors the reactants

a small Keq indicates the reaction

favors the products

a large Keq indicates the reaction

take the reciprocal

if you reverse a reaction, you _______________ the Keq

raise the Keq to the x power

if you multiply a balanced chem equation by a coefficient of x, you __________________ the Keq

multiply

if you add two reactions together, you ________________ the Keq

Q = [C]ᶜ[D]ᵈ / [A]ᵃ[B]ᵇ

(initial concentrations)

reaction quotient

favors the forward direction

if Q > Keq, the reaction

favors the reverse direction

if Q < Keq, the reaction

has no direction affinity

if Q = Keq, the reaction

le chartelier's principle

states that if a system at equilibrium is disturbed by a change in temperature, pressure, or a component concentration, the system will shift its equilibrium position so as to counteract the effect of the disturbance

the solubility product (Ksp)

the degree to which dissolution occurs

Ksp = [A⁺]ᵃ[B⁻]ᵇ

the solubility product

low solubility

a small Ksp value indicates

high solubility

a large Ksp value indicates

molar solubility

molarity of a solute in a saturated solution (S)

common ion

an ion that is common to two or more ionic compounds

common ion effect

If one of the ions in a solution equilibrium is already dissolved in the solution, the equilibrium will shift to the left and the solubility of the salt will decrease

exothermic reaction

ΔH < 0

endothermic reaction

ΔH > 0

left

if you raise the temperature of a exothermic reaction, the reaction will shift to the

right

if you lower the temperature of a exothermic reaction, the reaction will shift to the

right

if you raise the temperature of a endothermic reaction, the reaction will shift to the

left

if you lower the temperature of a endothermic reaction, the reaction will shift to the