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 2.10×10 M/s.

Write a balanced chemical equation for this reaction.

  • A N H ( ) N ( ) + 3 H ( ) 3 g g g
  • B 2 N H ( ) N ( ) + 6 H ( ) 3 2 g g g
  • C 3 N H ( ) 3 N ( ) + 2 H ( ) 3 2 g g g
  • D 2 N H ( ) 3 N ( ) + 3 H ( ) 3 2 2 g g g
  • E 2 N H ( ) N ( ) + 3 H ( ) 3 2 2 g g g

What is the rate of formation of nitrogen?

  • A 2 . 8 0 × 1 0 M/s
  • B 3 . 1 5 × 1 0 M/s
  • C 2 . 1 0 × 1 0 M/s
  • D 1 . 0 5 × 1 0 M/s
  • E 4 . 2 0 × 1 0 M/s

What is the rate of formation of hydrogen?

  • A 3 . 1 5 × 1 0 M/s
  • B 2 . 8 0 × 1 0 M/s
  • C 1 . 0 5 × 1 0 M/s
  • D 4 . 2 0 × 1 0 M/s
  • E 2 . 1 0 × 1 0 M/s

Q2:

Aqueous hydrogen peroxide (HO22) decomposes into oxygen and water. The rate of decomposition of hydrogen peroxide is found to be 3.20×10 M/h.

Write a balanced chemical equation for this reaction.

  • A H O ( ) 2 H O ( ) + 2 O ( ) 2 2 2 2 a q l g
  • B 2 H O ( ) H O ( ) + O ( ) 2 2 2 2 a q l g
  • C H O ( ) H O ( ) + O ( ) 2 2 2 a q l g
  • D 2 H O ( ) 2 H O ( ) + O ( ) 2 2 2 a q l g
  • E 2 H O ( ) 2 H O ( ) + O ( ) 2 2 2 2 a q l g

What is the rate of formation of water?

  • A 3 . 2 0 × 1 0 M/h
  • B 2 . 1 3 × 1 0 M/h
  • C 1 . 6 0 × 1 0 M/h
  • D 4 . 8 0 × 1 0 M/h
  • E 6 . 4 0 × 1 0 M/h

What is the rate of formation of oxygen?

  • A 6 . 4 0 × 1 0 M/h
  • B 2 . 1 3 × 1 0 M/h
  • C 4 . 8 0 × 1 0 M/h
  • D 1 . 6 0 × 1 0 M/h
  • E 3 . 2 0 × 1 0 M/h

Q3:

The equilibrium for the ionization of the HSO4 ion, a weak acid used in some household cleaners, is shown. HSO()+HO()HO()+SO()423+42aqlaqaq For a mixture of NaHSO4 and NaSO24 at equilibrium, the following are the concentrations:

  • [ H O ] = 0 . 0 2 7 M 3 + ,
  • [ H S O ] = 0 . 2 9 M 4 ,
  • [ S O ] = 0 . 1 3 M 4 2 .

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

  • A 2 . 2 × 1 0 M/s
  • B 1 . 0 × 1 0 M/s
  • C 8 . 2 × 1 0 M/s
  • D 1 . 9 × 1 0 M/s
  • E 2 . 2 × 1 0 M/s

Q4:

Dinitrogen pentoxide decomposes in chloroform to form nitrogen dioxide and oxygen, as shown. 2NO4NO+O2522 The decomposition is a first-order reaction with a rate constant of 6.20×10 min−1 at 45C. Calculate the rate of reaction in molars per second when [NO25] = 0.400 M.

  • A 2 . 4 8 × 1 0 M/s
  • B 4 . 1 3 × 1 0 M/s
  • C 6 . 8 9 × 1 0 M/s
  • D 2 . 5 8 × 1 0 M/s
  • E 1 . 0 3 × 1 0 M/s

Q5:

A reaction begins at a time 𝑡=0 and is monitored over a period of time, 𝑇, by measuring the reactant concentration, 𝐶, at fixed time intervals. How is the average rate of reaction for this time period calculated from a graph of 𝐶 against 𝑡?

  • ABy calculating the total area under the graph between 𝑡=0 and 𝑡=𝑇
  • BBy calculating the gradient of the tangent at 𝑡=𝑇
  • CBy fitting a polynomial function to the curve and evaluating the derivative of this function at 𝑡=𝑇
  • DBy calculating the gradient of the tangent at 𝑡=𝑇2
  • EBy dividing the change in 𝐶 between 𝑡=0 and 𝑡=𝑇 by 𝑇

Q6:

A reaction begins at a time 𝑡=0 and is monitored over a period of time, 𝑇, by measuring the reactant concentration, 𝐶, at fixed time intervals. How is the instantaneous rate at 𝑇 calculated from a graph of 𝐶 against 𝑡?

  • ABy dividing the change in 𝐶 between 𝑡=0 and 𝑡=𝑇 by 𝑇
  • BBy calculating the total area under the graph between 𝑡=0 and 𝑡=𝑇
  • CBy calculating the gradient of the tangent at 𝑡=𝑇
  • DBy fitting a polynomial function to the curve and evaluating the derivative of this function at 𝑡=𝑇
  • EBy calculating the gradient of the tangent at 𝑡=𝑇2

Nagwa uses cookies to ensure you get the best experience on our website. Learn more about our Privacy Policy.