lectures 5-7 chain reactions

Question 1

deriving rate law for multiple steps

Answer 1

write differential rate laws for each step (just k times everything on left hand side)
write balanced stoichiometric net equation of the mechanism
write any times the product comes up in the equation
simplify if there are intermediates

Question 2

what does pre-equilibrium mean

Answer 2

between 1 and -1 there is thermodynamic equilibrium which is almost not disturbed by reaction 2

Question 3

rate of product formation when fast equilibrium between A + M and A* + M

Answer 3

k^(2) K [A]

Question 4

what is boltzmann distribution

Answer 4

relationship between the concentrations of two levels is given by the exponential (-deltaE/RT)

Question 5

how to relate boltzman equation to rate law

Answer 5

a modified arrhenius equation

Question 6

what is the steady state approximation

Answer 6

there is equilibrium between production and consumption of X and concentration doesn’t change any more

Question 7

procedure for steady state approximation

Answer 7

collect all contributions to the change of [X] from elementary steps, set to 0 and solve

Question 8

limiting cases of lindermann mechanism

Answer 8

low pressure limit when M is small reaction order 2

when M is large order 1