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
18.5 g KMnO4​V = 750 mL

18.5 g of KMnO4 (M = 158.03 g/mol) is dissolved in water to make 750 mL of solution. Find the molarity c.

m = 18.5 gM = 158.03 g/molV = 750 mL
c = mol/L
2.Easy
10 g C6​H12​O6​V = 500 mL

10 g of C6H12O6 (M = 180.16 g/mol) is dissolved in water to make 500 mL of solution. Find the molarity c.

m = 10 gM = 180.16 g/molV = 500 mL
c = mol/L
3.Medium
6 mol/LV1​ = ?0.3 mol/L200 mL

You need 200 mL of 0.3 mol/L solution and have a 6 mol/L stock solution. What volume V1 of stock solution do you need?

c1 = 6 mol/Lc2 = 0.3 mol/LV2 = 200 mL
V1 = mL
4.Medium
5 mol/LV1​ = ?0.05 mol/L250 mL

You need 250 mL of 0.05 mol/L solution and have a 5 mol/L stock solution. What volume V1 of stock solution do you need?

c1 = 5 mol/Lc2 = 0.05 mol/LV2 = 250 mL
V1 = mL
5.Hard
2 mol/L50 mL0.6 mol/L200 mLc = ?250 mL

50 mL of a 2 mol/L solution is mixed with 200 mL of a 0.6 mol/L solution of the same substance. Find the concentration c of the mixture (volumes are additive).

c1 = 2 mol/LV1 = 50 mLc2 = 0.6 mol/LV2 = 200 mL
c = mol/L
6.Hard
1 mol/L100 mL0.75 mol/L400 mLc = ?500 mL

100 mL of a 1 mol/L solution is mixed with 400 mL of a 0.75 mol/L solution of the same substance. Find the concentration c of the mixture (volumes are additive).

c1 = 1 mol/LV1 = 100 mLc2 = 0.75 mol/LV2 = 400 mL
c = mol/L

Answer key

  1. 1. c = 0.1561 mol/L
  2. 2. c = 0.111 mol/L
  3. 3. V1 = 10 mL
  4. 4. V1 = 2.5 mL
  5. 5. c = 0.88 mol/L
  6. 6. c = 0.8 mol/L

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