Kinetics

Question 1

What is activation energy?

Answer 1

The minimum energy required for a reaction to occur

Question 2

What is the Arrhenius equation?

Answer 2

k = A * e ^ - (Ea/RT)

k - Rate constant
Ea - Activation energy in KJ/mol
T - Temperature in K
R - 8.314 in J/mol

Question 3

What are the factors that affect the rate constant value?

Answer 3

• Temperature
• Concentration of reactants

Question 4

What is zero order?

Answer 4

Means changing the concentration of the reactant has no effect on the rate

Question 5

What is 1st order?

Answer 5

The rate is directly proportional to the concentration of reactant

E.g. doubling the concentration will double the rate

Question 6

What is 2nd order?

Answer 6

The rate is proportional to the square of the concentration of reactant

E.g. doubling the concentration of reactant increases the rate by x4

Question 7

How to calculate half life for zero order?

Answer 7

t 1/2 = [A]₀ / 2k

Question 8

How to calculate half life for first order?

Answer 8

t 1/2 = ln (2) / k

Question 9

How to calculate half life for second order?

Answer 9

t 1/2 = 1 / k[A]₀

Question 10

How to work out how much faster a reaction is going at at two temperatures when A is constant:

Answer 10

1. Work out the difference in temperature by one
   E.g. 1/T1 and 1/T2
2. Work out Ea/R
3. Multiply the temperature difference by Ea/R
4. Use the answer to the exponent of e
   E.g. e^ the answer