Chemical kinetics Flashcards
First order rate constant (k)
k = (rate / [A]) s⁻¹
Rate equation
rate = k[A]ˣ[B]ʸ
Reaction order
sum of x + y
Zero order with respect to A
[A]⁰
As [A] doubles, rate acts independently
First order with respect to A
[A]
As [A] doubles, rate doubles
Second order with respect to A
[A]²
As [A] doubles, rate quadruples
Negative first order with respect to A
[A]⁻¹
As [A] doubles, rate decreases by a factor of 2
Half life of k[A]
half life = ln2 / k
Half life of k[A]²
half life = 1 / (k * [A]₀)
Half life of k[A]⁰
half life = [A]₀ / 2k
First order integrated rate law
ln[A]ₜ = -kt + ln[A]₀
ln ([A]ₜ / [A]₀) = -kt
Kinetic plots by reaction order
Zero: [A] vs. t
First: ln[A] vs. t
Second: 1/[A] vs. t
Pseudo-first-order reaction
True second order
A + B —> product
rate = k[A][B]
Zero order integrated rate law
[A]ₜ = -kt + [A]₀
Second order integrated rate law (A —> products only)
(1 / [A]ₜ) = kt + (1 / [A]₀)
