What mass m of CuSO4 (M = 159.61 g/mol) do you need to make 750 mL of a 0.2 mol/L solution?
Molarity & dilution worksheet with answers
1.Easy
V = 750 mLc = 0.2 mol/LM = 159.61 g/mol
m = g
2.Easy
14 g of NaCl (M = 58.44 g/mol) is dissolved in water to make 200 mL of solution. Find the molarity c.
m = 14 gM = 58.44 g/molV = 200 mL
c = mol/L
3.Medium
You need 100 mL of 0.5 mol/L solution and have a 2 mol/L stock solution. What volume V1 of stock solution do you need?
c1 = 2 mol/Lc2 = 0.5 mol/LV2 = 100 mL
V1 = mL
4.Medium
You need 200 mL of 0.25 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 = 0.25 mol/LV2 = 200 mL
Vwater = mL
5.Hard
50 mL of a 0.25 mol/L solution is mixed with 500 mL of a 1.2 mol/L solution of the same substance. Find the concentration c of the mixture (volumes are additive).
c1 = 0.25 mol/LV1 = 50 mLc2 = 1.2 mol/LV2 = 500 mL
c = mol/L
6.Hard
100 mL of a 0.5 mol/L solution is mixed with 200 mL of a 0.75 mol/L solution of the same substance. Find the concentration c of the mixture (volumes are additive).
c1 = 0.5 mol/LV1 = 100 mLc2 = 0.75 mol/LV2 = 200 mL
c = mol/L
Answer key
- 1. m = 23.94 g
- 2. c = 1.198 mol/L
- 3. V1 = 25 mL
- 4. Vwater = 100 mL
- 5. c = 1.114 mol/L
- 6. c = 0.6667 mol/L
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