Colligative properties can be sources of insight into not only the properties of solutions, but also the properties of the solute. For example, acetic acid, CH₃COOH, behaves differently in two different solvents.

(a) The freezing point of a 5.00% by mass aqueous acetic acid solution is –1.72°C. What is the molar mass of the solute? Explain any discrepancy between the experimental and the expected molar mass.

(b) The freezing-point depression associated with a 5.00% by mass solution of acetic acid in benzene is 2.32°C. What is the experimental molar mass of the solute in benzene? What can you conclude about the nature of acetic acid in benzene?