# Worksheet: Reaction Rates

In this worksheet, we will practice calculating reaction rates using variables such as concentration, pressure, conductivity, and optical absorption.

Q1:

Ammonia decomposes into hydrogen and nitrogen at high temperature. The rate of decomposition of ammonia is found to be M/s.

Write a balanced chemical equation for this reaction.

• A
• B
• C
• D
• E

What is the rate of formation of nitrogen?

• A M/s
• B M/s
• C M/s
• D M/s
• E M/s

What is the rate of formation of hydrogen?

• A M/s
• B M/s
• C M/s
• D M/s
• E M/s

Q2:

Aqueous hydrogen peroxide () decomposes into oxygen and water. The rate of decomposition of hydrogen peroxide is found to be M/h.

Write a balanced chemical equation for this reaction.

• A
• B
• C
• D
• E

What is the rate of formation of water?

• A M/h
• B M/h
• C M/h
• D M/h
• E M/h

What is the rate of formation of oxygen?

• A M/h
• B M/h
• C M/h
• D M/h
• E M/h

Q3:

The equilibrium for the ionization of the ion, a weak acid used in some household cleaners, is shown. For a mixture of and at equilibrium, the following are the concentrations:

• ,
• ,
• .

What is the equilibrium constant for this reaction under these conditions?

• A M/s
• B M/s
• C M/s
• D M/s
• E M/s

Q4:

Dinitrogen pentoxide decomposes in chloroform to form nitrogen dioxide and oxygen, as shown. The decomposition is a first-order reaction with a rate constant of min−1 at . Calculate the rate of reaction in molars per second when [] = 0.400 M.

• A M/s
• B M/s
• C M/s
• D M/s
• E M/s

Q5:

A reaction begins at a time and is monitored over a period of time, , by measuring the reactant concentration, , at fixed time intervals. How is the average rate of reaction for this time period calculated from a graph of against ?

• ABy calculating the total area under the graph between and
• BBy calculating the gradient of the tangent at
• CBy fitting a polynomial function to the curve and evaluating the derivative of this function at
• DBy calculating the gradient of the tangent at
• EBy dividing the change in between and by

Q6:

A reaction begins at a time and is monitored over a period of time, , by measuring the reactant concentration, , at fixed time intervals. How is the instantaneous rate at calculated from a graph of against ?

• ABy dividing the change in between and by
• BBy calculating the total area under the graph between and
• CBy calculating the gradient of the tangent at
• DBy fitting a polynomial function to the curve and evaluating the derivative of this function at
• EBy calculating the gradient of the tangent at