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.

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1.Easy
200 mLc = 0.2 mol/L

What mass m of CuSO4 (M = 159.61 g/mol) do you need to make 200 mL of a 0.2 mol/L solution?

V = 200 mLc = 0.2 mol/LM = 159.61 g/mol
m = g
2.Easy
22 g KMnO4​V = 200 mL

22 g of KMnO4 (M = 158.03 g/mol) is dissolved in water to make 200 mL of solution. Find the molarity c.

m = 22 gM = 158.03 g/molV = 200 mL
c = mol/L
3.Medium
1.5 mol/LV1​0.05 mol/L200 mL

You need 200 mL of 0.05 mol/L solution and have a 1.5 mol/L stock solution. How much water Vwater do you add to the stock solution?

c1 = 1.5 mol/Lc2 = 0.05 mol/LV2 = 200 mL
Vwater = mL
4.Medium
5 mol/LV1​ = ?0.1 mol/L250 mL

You need 250 mL of 0.1 mol/L solution and have a 5 mol/L stock solution. What volume V1 of stock solution do you need?

c1 = 5 mol/Lc2 = 0.1 mol/LV2 = 250 mL
V1 = mL
5.Hard
2 mol/L200 mL0.3 mol/L400 mLc = ?600 mL

200 mL of a 2 mol/L solution is mixed with 400 mL of a 0.3 mol/L solution of the same substance. Find the concentration c of the mixture (volumes are additive).

c1 = 2 mol/LV1 = 200 mLc2 = 0.3 mol/LV2 = 400 mL
c = mol/L
6.Hard
0.25 mol/L50 mL3 mol/L500 mLc = ?550 mL

50 mL of a 0.25 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 = 0.25 mol/LV1 = 50 mLc2 = 3 mol/LV2 = 500 mL
c = mol/L

Answer key

  1. 1. m = 6.384 g
  2. 2. c = 0.6961 mol/L
  3. 3. Vwater = 193.3 mL
  4. 4. V1 = 5 mL
  5. 5. c = 0.8667 mol/L
  6. 6. c = 2.75 mol/L

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