JEE Mains · Chemistry · STD 12 -1. Solution and colligative properties
A \(0.5\) percent solution of potassium chloride was found to freeze at \(-0.24^{\circ} C\). The percentage dissociation of potassium chloride is .... (Nearest integer) (Molal depression constant for water is \(1.80\, K\, kg\,mol ^{-1}\) and molar mass of \(KCl\) is \(74.6 \,g\, mol ^{-1}\) )
- A \(41\)
- B \(60\)
- C \(80\)
- D \(98.5\)
Answer & Solution
Correct Answer
(D) \(98.5\)
Step-by-step Solution
Detailed explanation
\(0.5\, \%\) solution of \(KCl\) So \(m =\frac{0.5}{74.6} \times \frac{1}{0.1}\) \(\Delta T _{ f }= i \times m _{ f }\) \(0.24=i \cdot \frac{0.5}{74.6} \times \frac{1.80}{0.1}\) \(i=\frac{0.24 \times 74.6}{0.5 \times 1.80} \times 0.1\) \(=1.989\) \(1.989=1+\alpha( n -1)\)…
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