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
16 g NaOHV = 1000 mL

16 g of NaOH (M = 40 g/mol) is dissolved in water to make 1000 mL of solution. Find the molarity c.

m = 16 gM = 40 g/molV = 1000 mL
c = mol/L
2.Easy
13.5 g CuSO4​V = 750 mL

13.5 g of CuSO4 (M = 159.61 g/mol) is dissolved in water to make 750 mL of solution. Find the molarity c.

m = 13.5 gM = 159.61 g/molV = 750 mL
c = mol/L
3.Medium
3 mol/LV1​0.4 mol/L250 mL

You need 250 mL of 0.4 mol/L solution and have a 3 mol/L stock solution. How much water Vwater do you add to the stock solution?

c1 = 3 mol/Lc2 = 0.4 mol/LV2 = 250 mL
Vwater = mL
4.Medium
3 mol/LV1​ = ?0.3 mol/L200 mL

You need 200 mL of 0.3 mol/L solution and have a 3 mol/L stock solution. What volume V1 of stock solution do you need?

c1 = 3 mol/Lc2 = 0.3 mol/LV2 = 200 mL
V1 = mL
5.Hard
0.25 mol/L250 mL0.05 mol/L200 mLc = ?450 mL

250 mL of a 0.25 mol/L solution is mixed with 200 mL of a 0.05 mol/L solution of the same substance. Find the concentration c of the mixture (volumes are additive).

c1 = 0.25 mol/LV1 = 250 mLc2 = 0.05 mol/LV2 = 200 mL
c = mol/L
6.Hard
0.1 mol/L300 mL3 mol/L500 mLc = ?800 mL

300 mL of a 0.1 mol/L solution is mixed with 500 mL of a 3 mol/L solution of the same substance. Find the concentration c of the mixture (volumes are additive).

c1 = 0.1 mol/LV1 = 300 mLc2 = 3 mol/LV2 = 500 mL
c = mol/L

Answer key

  1. 1. c = 0.4 mol/L
  2. 2. c = 0.1128 mol/L
  3. 3. Vwater = 216.7 mL
  4. 4. V1 = 20 mL
  5. 5. c = 0.1611 mol/L
  6. 6. c = 1.913 mol/L

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