What is the molarity of a solution prepared by dissolving 10.7 g of NaI in 0.250 L of solution? (Molar mass of NaI = 149.89 g/mol)

• A. 0.0715 M
• B. 0.715 M
• C. 0.179 M
• D. 0.286 M

Answer: (D)

Verified step by step guidance

1. Identify the given information: mass of NaI = 10.7 g, volume of solution = 0.250 L, and molar mass of NaI = 149.89 g/mol.
2. Calculate the number of moles of NaI using the formula: \(\text{moles} = \frac{\text{mass}}{\text{molar mass}} = \frac{10.7\ \text{g}}{149.89\ \text{g/mol}}\).
3. Use the definition of molarity, which is moles of solute per liter of solution: \(M = \frac{\text{moles of solute}}{\text{volume of solution in liters}}\).
4. Substitute the calculated moles and the given volume into the molarity formula: \(M = \frac{\text{moles}}{0.250\ \text{L}}\).
5. Perform the division to find the molarity of the NaI solution.