Question

What is the molarity of a solution prepared by dissolving 8.67 g of potassium iodide, KI, in 250 mL of water (The molar mass of KI is 166 g/mol.)

Answer 1

$$n(KI) = m/M = 8.67/166 = 0.05 mol$$

$$c = n/V = 0.05/0.25 = 0.2M$$