AP Chemistry Unit 5 Chemical Kinetics

NOT COMPLETED

difference between thermodynamics and kinetics

thermodynamics - does a reaction take place?

kinetics - how fast does a reaction proceed?

reaction rate

change in concentration of a reactant or a product with time

instantaneous rate

rate for specific instance in time

rate law

expresses the relationship of the rate of a reaction to the rate constant and the concentrations of the reactants raised to some powers

the rate law

k[A]^x[B]^y

reaction is xth order in A

reaction is yth order in B

reaction is (x+y)th order overall

true or false: rate laws are always determined experimentally

true

true or false: reaction order is not always defined in terms of reactant concentrations.

false

true or false: the order of a reaction is directly related to the stoichiometric coefficient of the reactant in the balanced chemical equation

false

half life definition

time required for concentration of a reactant to decrease to half of its initial concentration

reaction rate formulas

rate law for zero order reaction

rate = k

rate law for first order reaction

rate = k [A]

rate law for second order reaction

rate = k [A]²

concentration-time equation for zero order reaction

concentration-time equation for first order reaction

concentration-time equation for second order reaction

half-life for zero order reaction

half-life for first order reaction

or 0.693/k

half-life for second order reaction

activation energy

minimum amount of energy required to initiate a chemical reaction

endothermic reaction

more energy is absorbed when the bonds in the reactants are broken than is released when new bonds are formed in the products

exothermic reaction

more energy is released when the bonds are formed in the products than is used to break the bonds in the reactants

arrhenius equation

what is the arrhenius equation used for

to determine the effect of a change of temperature on the rate constant

units for rate

(ms)^-1

units for k in first order reaction

1/s

units for k in second order reaction

1/ms