Question

Which of the following solutions will show highest freezing point depression?

• A. 1 M glucose
• B. 1 M NaCl
• C. 1 M AlCl3
• D. 1 M MgCl2

Hint:

The more particles a solute produces in solution, the higher the freezing point depression.

Answer 1

The Correct Option is C

Freezing point depression is proportional to the number of dissolved particles. The van't Hoff factor, denoted by \(i\), quantifies the number of particles a solute dissociates into. For 1 M solutions:
- Glucose, a non-dissociating solute, has \(i = 1\).
- NaCl dissociates into two ions, resulting in \(i = 2\).
- AlCl3 dissociates into four ions, giving \(i = 4\).
- MgCl2 dissociates into three ions, with \(i = 3\).
Consequently, AlCl3 will induce the most significant freezing point depression due to its highest ion production.