Orders, rate equations and rate constants

Question 1

What is the equation for the rate of a reaction?

Answer 1

Change in concentration/time

Question 2

What are the units?

Answer 2

Concentration = moldm-3
rate = moldm-3S-1

Question 3

What is a zero order reactant?

Answer 3

When the concentration of a reactant has no effect on rate, the reactant is 0 order
rate is directly proportional to (A)0

Question 4

What is a first order reactant?

Answer 4

When a reactant is first order, when the concentration of the reactant increases the rate increases by an equivalent rate
rate = (A)1
Therefore if the concentration of a reactant is doubled, rate increases by a factor of two

Question 5

What is a second order reactant?

Answer 5

When a reactant is in second order, when it increases the rate increases by a factor of 2
rate = (A)2
If the concentration of a reactant is doubled, rate increases by 4

Question 6

What is the rate equation?

Answer 6

rate = k(A)n (B)n

Question 7

What is the rate constant?

Answer 7

The proportionality constant
This number mathematically converts between the rate of reaction and the concentration of orders

Question 8

How do you calculate the rate constant?

Answer 8

k = rate/ reactant orders
find units by cancelling them out

Question 9

How do you calculate the overall order?

Answer 9

The sum of orders in respect to the orders of reactants

Question 10

How do you find the orders of reactants experimentally?

Answer 10

Using the initial rate method, change the concentration of one reactants and keep everything else constant

Observe the changes in the initial rate of reaction

Repeat for the other reactants