Calculate the molality of aqueous solution of electrolyte that freezes at -0.93 ,^ C if K_f for water and van't Hoff factor respectively are 1.86 , K kg mol ⁻¹ and 1.25 . (Freezing point of water = 0 ,^ C )

Step-by-step solution

The depression in freezing point is given by the formula: T_f = i K_f m Given: Freezing point of solution, T_f = -0.93 ,^ C Freezing point of water, T_f^ = 0 ,^ C T_f = T_f^ - T_f = 0 - (-0.93) = 0.93 ,^ C van't Hoff factor, i = 1.25 Cryoscopic constant, K_f = 1.86 , K kg mol ⁻¹ Substituting the values into the formula: 0.93 = 1.25 1.86 m m = 0.93 1.25 1.86 m = 0.5 1.25 = 0.4 , m Answer: 0.4 m