How many moles of KI are required to prepare 0.50 L of a 0.20 M aqueous solution?

• A. 0.10 mol
• B. 0.05 mol
• C. 0.20 mol
• D. 0.40 mol

Answer: (A)

Verified step by step guidance

1. Identify the formula relating molarity (M), moles of solute (n), and volume of solution (V): \(M = \frac{n}{V}\).
2. Rearrange the formula to solve for moles of solute: \(n = M \times V\).
3. Substitute the given values into the equation: \(M = 0.20\, \text{mol/L}\) and \(V = 0.50\, \text{L}\).
4. Calculate the moles of KI needed by multiplying the molarity by the volume: \(n = 0.20 \times 0.50\).
5. Interpret the result as the number of moles of KI required to prepare the solution.