# Worksheet: Reaction Rates

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:

A reaction begins at a time = 0 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 calculating the total area under the graph between = 0 and =
• BBy fitting a polynomial function to the curve and evaluating the derivative of this function at =
• CBy dividing the change in between = 0 and = by
• DBy calculating the gradient of the tangent at =
• EBy calculating the gradient of the tangent at =

Q3:

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

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

Q4:

A reaction begins at a time = 0 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 = 0 and =
• BBy fitting a polynomial function to the curve and evaluating the derivative of this function at =
• CBy calculating the gradient of the tangent at =
• DBy dividing the change in between = 0 and = by
• EBy calculating the gradient of the tangent at =

Q5:

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

Q6:

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

= 0.027 M,

= 0.29 M,

= 0.13 M.

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