Question

Which of the following is not a colligative property?

• A. $\Delta T_{f}$
• B. $\pi$
• C. $\Delta T_{b}$
• D. $K_{b}$

Answer 1

Answer: (D)

The colligative properties are those which depend on number of particles but not on their nature.
$\Delta T_{f}$ (depression in freezing point),
$\pi$ (osmotic pressure),
$\Delta T_{b}$ (elevation in boiling point)
are colligative properties.
$K_{b}$ is molal elevation constant and it is not colligative property.