Molarity & dilution worksheet with answers

Free printable Molarity & dilution 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
250 mLc = 0.5 mol/L

What mass m of CuSO4 (M = 159.61 g/mol) do you need to make 250 mL of a 0.5 mol/L solution?

V = 250 mLc = 0.5 mol/LM = 159.61 g/mol
m = g
2.Easy
500 mLc = 0.2 mol/L

What mass m of CaCl2 (M = 110.98 g/mol) do you need to make 500 mL of a 0.2 mol/L solution?

V = 500 mLc = 0.2 mol/LM = 110.98 g/mol
m = g
3.Medium
2.5 mol/LV1​ = ?0.3 mol/L1000 mL

You need 1000 mL of 0.3 mol/L solution and have a 2.5 mol/L stock solution. What volume V1 of stock solution do you need?

c1 = 2.5 mol/Lc2 = 0.3 mol/LV2 = 1000 mL
V1 = mL
4.Medium
2.5 mol/LV1​ = ?0.4 mol/L200 mL

You need 200 mL of 0.4 mol/L solution and have a 2.5 mol/L stock solution. What volume V1 of stock solution do you need?

c1 = 2.5 mol/Lc2 = 0.4 mol/LV2 = 200 mL
V1 = mL
5.Hard
1 mol/L150 mL0.1 mol/L100 mLc = ?250 mL

150 mL of a 1 mol/L solution is mixed with 100 mL of a 0.1 mol/L solution of the same substance. Find the concentration c of the mixture (volumes are additive).

c1 = 1 mol/LV1 = 150 mLc2 = 0.1 mol/LV2 = 100 mL
c = mol/L
6.Hard
0.5 mol/L100 mL0.05 mol/L50 mLc = ?150 mL

100 mL of a 0.5 mol/L solution is mixed with 50 mL of a 0.05 mol/L solution of the same substance. Find the concentration c of the mixture (volumes are additive).

c1 = 0.5 mol/LV1 = 100 mLc2 = 0.05 mol/LV2 = 50 mL
c = mol/L

Answer key

  1. 1. m = 19.95 g
  2. 2. m = 11.1 g
  3. 3. V1 = 120 mL
  4. 4. V1 = 32 mL
  5. 5. c = 0.64 mol/L
  6. 6. c = 0.35 mol/L

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