Amide hydrolysis yields sodium carboxylate and ammonia

Steps:

• Identify reaction as CH₃CONH₂ + NaOH → CH₃COONa + NH₃ (ethanethiol likely misstated as ethanamide).
• Moles of CH₃COONa theoretically produced: 0.200 mol (1:1 stoichiometry).
• Molar mass of CH₃COONa: 82 g/mol; theoretical mass: 0.200 × 82 = 16.4 g.
• Actual mass at 80% yield: 16.4 × 0.80 = 13.12 g ≈ 13 g.

Why B is correct:

• Matches calculated mass of S (CH₃COONa) after applying 80% yield to theoretical 16.4 g.

Why the others are wrong:

• A: Underestimates yield (e.g., 50% would be ~8.2 g, not 80%).
• C: Assumes ~92% yield (15/16.4 ≈ 0.91), exceeding 80%.
• D: Theoretical mass without yield adjustment (16.4 g rounded).

Final answer: B