Practice question
Question
A 250 mL solution contains 4.8 g of NaCl and has a density of 1.02 g/mL. What is the molarity? (Molar mass: NaCl = 58.5 g/mol)
Explanation
Moles of NaCl = 4.8/58.5 ≈ 0.0821 mol. Volume = 0.25 L. Molarity = 0.0821/0.25 ≈ 0.328 M.