1. Progress of Chemical Reactions

2. Rate Laws
An expression for the rate of a reaction in terms of the concentrations of the reactants
Equation: A  B rate = k[A]
k is a constant

3. Rate Constant
Specific rate constant (k): a proportionality constant relating the concentration of the reactants to the reaction rate
k is large is the products form quickly
k is small is the products form slowly

4. Order of Reaction
First order reactions: the reaction rate is directly proportional to the concentration of one reactant
The exponent for that reactant is 1
Half the concentration, half the rate
Rate = k[A][B]
Reaction is first order in A and B

5. First Order Reaction

6. Order of Reactions
Reactions can be second or third order, with the reactants raised to the power of 2 & 3 respectively.
Order of reaction is determined experimentally.
9 out of 10: coefficient will be the exponent
aA + bB  cC rate = [A]a[B]b
Overall order of the reaction is the sum of the exponents for the individual reactants
2N2O  2N2 + O2 rate = [N2O]2
Overall order: 2
2N2 + O2  2N2O rate = [N2]2[O2]
Overall order: 3

7. Second Order Reactions

8. Reaction Mechanisms Elementary Rxn:
Reactants Products in 1 step
1 activation energy peak
Reaction Mechanism: series of elementary reactions
Reaction progress is a series of peaks and valley
Peaks: activation energy
Valley: energy of intermediates
Intermediate: product of the steps in the reaction mechanism
N2O  N2 + O
N2O + O  N2 + O2
2N2O  2N2 +O2

10. Reaction Mechanisms

11. Reaction Mechanism