The unit of Boiling point Elevation Constant ($K_b$) is
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → $K\, kg\, mol^{-1}$
- Boiling point elevation is given by:
$\Delta T_b = K_b \cdot m$
where:
- $\Delta T_b$ = elevation in boiling point (K)
- m = molality of solute (mol/kg)
Rearranging for Kb:
$K_b = \frac{\Delta T_b}{m} ⇒\text{units of } K_b = \frac{\text{K}}{\text{mol/kg}} = \text{K·kg·mol}^{-1}$
Hence, the unit is K·kg·mol-1.