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
13 g KNO3​V = 150 mL

13 g of KNO3 (M = 101.1 g/mol) is dissolved in water to make 150 mL of solution. Find the molarity c.

m = 13 gM = 101.1 g/molV = 150 mL
c = mol/L
2.Easy
13.5 g CaCl2​V = 250 mL

13.5 g of CaCl2 (M = 110.98 g/mol) is dissolved in water to make 250 mL of solution. Find the molarity c.

m = 13.5 gM = 110.98 g/molV = 250 mL
c = mol/L
3.Medium
0.5 mol/LV1​0.1 mol/L200 mL

You need 200 mL of 0.1 mol/L solution and have a 0.5 mol/L stock solution. How much water Vwater do you add to the stock solution?

c1 = 0.5 mol/Lc2 = 0.1 mol/LV2 = 200 mL
Vwater = mL
4.Medium
4 mol/LV1​0.4 mol/L100 mL

You need 100 mL of 0.4 mol/L solution and have a 4 mol/L stock solution. How much water Vwater do you add to the stock solution?

c1 = 4 mol/Lc2 = 0.4 mol/LV2 = 100 mL
Vwater = mL
5.Hard
1.5 mol/L150 mL1.2 mol/L200 mLc = ?350 mL

150 mL of a 1.5 mol/L solution is mixed with 200 mL of a 1.2 mol/L solution of the same substance. Find the concentration c of the mixture (volumes are additive).

c1 = 1.5 mol/LV1 = 150 mLc2 = 1.2 mol/LV2 = 200 mL
c = mol/L
6.Hard
1.5 mol/L150 mL0.05 mol/L400 mLc = ?550 mL

150 mL of a 1.5 mol/L solution is mixed with 400 mL of a 0.05 mol/L solution of the same substance. Find the concentration c of the mixture (volumes are additive).

c1 = 1.5 mol/LV1 = 150 mLc2 = 0.05 mol/LV2 = 400 mL
c = mol/L

Answer key

  1. 1. c = 0.8572 mol/L
  2. 2. c = 0.4866 mol/L
  3. 3. Vwater = 160 mL
  4. 4. Vwater = 90 mL
  5. 5. c = 1.329 mol/L
  6. 6. c = 0.4455 mol/L

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