Question

What is the depression in the freezing point?

• A. \( \Delta T_f = K_f \times m \)
• B. \( \Delta T_f = K_b \times m \)
• C. \( \Delta T_f = m \times 100 \)
• D. \( \Delta T_f = K_f \times \frac{1}{m} \)

Hint:

The depression in freezing point is a colligative property, meaning it depends on the number of solute particles in the solution, not their identity.

Answer 1

The Correct Option is A

The depression in freezing point (\( \Delta T_f \)) is given by the formula: \[ \Delta T_f = K_f \times m \] where: - \( K_f \) is the cryoscopic constant or freezing point depression constant of the solvent, and - \( m \) is the molality of the solution (moles of solute per kilogram of solvent). This formula shows that the depression in freezing point is directly proportional to the molality of the solution.