The normal freezing point of nitrobenzene is 278.82 K. A non-volatile solute is dissolved in it and — Solutions and Colligative Properties Chemistry Question

💡 Solution & Explanation

The freezing point depression $\Delta T_f = 278.82 - 276.82 = 2.00 \text{ K}$. Given molality $m = 0.25 \text{ m}$. Using the formula $\Delta T_f = K_f \times m$, we have $K_f = \Delta T_f / m = 2.00 / 0.25 = 8.0 \text{ K-kg mol}^{-1}$. Therefore, correct answer is B.