Reaction kinetics worksheet with answers

Free printable Reaction kinetics worksheet: 6 problems from easy to exam level, with an answer key. Print it or save it as a PDF.

New worksheetPractise online with hints

For teachers: free to print, copy and use in class. Every new worksheet has new values and its own answer key. A link to ExamProblems on your course page is appreciated.

Name: ____________________   Date: ____________

1.Easy
t (min)C (mol/L)10 minC = ?

A first-order reaction A → products has a rate constant of 0.2 min⁻¹. The initial concentration of A is 0.5 mol/L. Find the concentration CA after 10 min.

k = 0.2 min⁻¹CA0 = 0.5 mol/Lt = 10 min
CA = mol/L
2.Easy
t (min)C (mol/L)t½​ = ?C0​/2

A first-order reaction has a rate constant of 0.25 min⁻¹. Find its half-life t½.

k = 0.25 min⁻¹
t½ = min
3.Medium
t (min)X (%)t = ?99%

A first-order reaction in a batch reactor has k = 0.01 min⁻¹. How long does it take to reach 99% conversion? Find t.

k = 0.01 min⁻¹X = 99 %
t = min
4.Medium
t (min)X (%)t = ?60%

A first-order reaction in a batch reactor has k = 0.1 min⁻¹. How long does it take to reach 60% conversion? Find t.

k = 0.1 min⁻¹X = 60 %
t = min
5.Hard
t (min)X (%)20 minX = ?

A first-order reaction has k = 0.005 min⁻¹ at 25 °C and an activation energy of 60 kJ/mol. The batch reactor is now run at 50 °C for 20 min. Find the conversion X reached.

k1 = 0.005 min⁻¹T1 = 25 °CEa = 60 kJ/molT2 = 50 °Ct = 20 minR = 8.314 J/(mol·K)
X = %
6.Hard
1/Tln kT = 40 °Cln 0.001ln A = ?Ea​ = 60 kJ/mol

A first-order reaction has a rate constant of 0.001 s⁻¹ at 40 °C and an activation energy of 60 kJ/mol. Find the pre-exponential factor A in the Arrhenius equation.

k = 0.001 s⁻¹T = 40 °CEa = 60 kJ/molR = 8.314 J/(mol·K)
A = s⁻¹

Answer key

  1. 1. CA = 0.06767 mol/L
  2. 2. t½ = 2.773 min
  3. 3. t = 460.5 min
  4. 4. t = 9.163 min
  5. 5. X = 47.82 %
  6. 6. A = 1.02 × 10⁷ s⁻¹

Full step-by-step solutions: practise this topic on examproblems.com.