What mass of NaOH (molar mass = 40 g/mol) is required to prepare 500 mL of 0.2 M solution?
Q1. What mass of NaOH (molar mass = 40 g/mol) is required to prepare 500 mL of 0.2 M solution?
Answer: 4 g
Explanation: 0.5 L × 0.2 mol/L × 40 g/mol = 4 g. Option C halves volume incorrectly.