The immiscible liquid system containing aniline-water boils at 98°C under a pressure of 760 mm. At t — Solutions and Colligative Properties Chemistry Question

💡 Solution & Explanation

Vapour pressure of aniline = $760 - 700 = 60$ mm. Mass ratio $W_A / W_W = (P_A \cdot M_A) / (P_W \cdot M_W) = (60 \cdot 93) / (700 \cdot 18) = 5580 / 12600 = 0.4428$. Mass % of aniline = $0.4428 / (1 + 0.4428) \times 100 = 0.4428 / 1.4428 \times 100 \approx 30.7\%$. Therefore, correct answer is C.