'' moles of KCl and '' mole of are dissolved in 1 kg of water. If , then the observed range of is ( — Solutions and Colligative Properties Chemistry Question

💡 Solution & Explanation

KCl dissociates into 2 ions ($i=2$) and $\text{BaCl}_2$ into 3 ions ($i=3$). Total moles of particles = $2x + 3y$. The extremes occur when $x=0.1, y=0$ or $x=0, y=0.1$. If $x=0.1, y=0$, total particles = 0.2 mol, giving $\Delta T_f = 1.86 \times 0.2 = 0.372^\circ\text{C}$. If $x=0, y=0.1$, total particles = 0.3 mol, giving $\Delta T_f = 1.86 \times 0.3 = 0.558^\circ\text{C}$. The range is $0.372^\circ\text{C}$ to $0.558^\circ\text{C}$. Therefore, correct answer is A.