Chemical Kinetics and Equilibrium

Question 1

Zero Order Reaction

Answer 1

m = 0
R = k
[A] = [A]0 - kt
t1/2 = [A]0 / 2k
Unit of rate constant = M/s
- slope

Question 2

First Order Reaction

Answer 2

m = 1
R = k[A]
[A] = [A]0 x e^-kt
t1/2 = ln(2) / k
Unit of rate constant = 1/s
- slope

Question 3

Second Order Reaction

Answer 3

m = 2
R = k[A]^2
1/[A] = 1/[A]0 + kt
t1/2 = 1/k[A]0
Unit of rate constant = 1/Ms
\+ slope

Question 4

Reaction Order and Michaelis-Menten Curve at low substrate concentrations

Answer 4

The reaction is approximately first order

Question 5

Reaction Order and Michaelis-Menten Curve at high substrate concentration

Answer 5

The reaction approximates zero-order since the reaction ceases to depend on substrate concentration.

Question 6

Arrhenius Equation

Answer 6

k = A x e(-Ea/RT)

Question 7

Definition of Rate: For aA + bB –> cC + dD

Answer 7

Rate = - delta[A] / a delta t = -delta[B] / b delta t = delta[C] / c delta t = delta[D] / d delta t

Question 8

Rate Law

Answer 8

rate = k [A]^x [B]^y

Question 9

Radioactive Decay

Answer 9

[A]t = [A]0 x e^kt

Question 10

Overall Reaction Mechanism

Answer 10

A2 + 2B –> 2AB
Step 1: A2 + B –> A2B (slow)
Step 2: A2B + B –> 2AB (fast)

Question 11

Slow step is the ___ ________ step.

Answer 11

Rate determining

Question 12

As A increases, k…

Answer 12

Increases

Question 13

As T increases, k…

Answer 13

increases

Question 14

Gibbs Free Energy

Answer 14

Delta G = Ea - Ea rev

Question 15

-Delta G

Answer 15

Exergonic

Question 16

+Delta G

Answer 16

Endergonic

Question 17

Equilibrium Constant (Keq)

Answer 17

[C]^c [D]^d / [A]^a [B]^b

Question 18

Reaction Quotient (Qc)

Answer 18

[C]^c [D]^d / [A]^a [B]^b

Question 19

When Q < Keq, the reaction…

Answer 19

proceeds to the right (Delta G< 0)

Question 20

When Q = Keq, the reaction is

Answer 20

At equilibrium. Delta G = 0

Question 21

When Q > Keq, the reaction

Answer 21

proceeds to the left. (Delta G> 0)

Question 22

Kinetic Products

Answer 22

Higher in free energy than thermodynamic products and can form at lower temperatures. “Fast” products because they can form more quickly under such conditions.

Question 23

Thermodynamic Products

Answer 23

Lower in free energy than kinetic products, more stable. Slower but more spontaneous (more negative delta G).

Question 24

Le Chatelier’s Principle

Answer 24

If a stress is applied to a system, the system shifts to relieve that applied stress.

Question 25

Lower pH

Answer 25

Increases respiration to blow off CO2

Question 26

Higher pH

Answer 26

Lowers respiration, trapping CO2