chem kinetics

Chemical Kinetics

Study of factors that affect the rates of chemical reactions and the mechanisms (series of steps) by which reactions take place. 

Rxn Rate

the # of atoms, ions, or mlc that react in a given time to form products. 

rxn rate equation

change in [reactant]/change in time

factors that change rate of rxn

Temp, Concentration, agitation, catalyst. Particle size, nature and physical states (Types of bonds). 

Collision Theory

particles must collide in order to react and must be effective and have proper orientation in order to collide. 

Activation Energy

the minimum energy that colliding particles must have in order to react. 

Equilibrium

rate of when the forward rxn is equal to rate of the reverse reaction.

characteristics of equilibrium

When a rxn reaches equilibrium, concentrations of reactants and products are constant, Doesn't stop moving but are at constant, Starts right when stop changing

K

equilibrum constant (TEMP DEPENDENT)

k>>1

products are favored and reaction goe sto completion

k<<1

reactants are favored and the reaction does not proceed significantly toward products.

K~1

neither reactants or products are favored and usually a lot of products and reactants are at equilibrium

Le Chatliers Principle

 If a “stress/change” is applied to a reaction that is at equilibrium the rxn shifts to relieve the stress. 

types of stress (le Chat)

Change concentrations of reactant/product, change temp (adding or removing heat), change pressure (gas only) by increasing or decreasing the volume.