Q21 / 160 · AP EAMCET 2024 (19 May Shift 2) · Chemistry
The $\Delta \mathrm{T}_{\mathrm{b}}$ value for 0.01 m KCI solution is 0.01 K . What is the Van't Hoff factor?
$\left(\mathrm{K}_{\mathrm{b}} \text { for water }=0.52 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}\right)$
- Correct answerA1.92
- B1.72
- C0.96
- D0.86
Solution
Given, $\Delta \mathrm{T}_{\mathrm{b}}=0.01 \mathrm{~K}$
Molality $=0.01 \mathrm{~m}$
$\mathrm{K}_{\mathrm{b}}=0.52 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}$
We know, $\Delta \mathrm{T}_{\mathrm{b}}=\mathrm{i} \mathrm{K}_{\mathrm{b}} \mathrm{m}$
$\mathrm{i}=\frac{\Delta \mathrm{T}_{\mathrm{b}}}{\mathrm{~K}_{\mathrm{b}} \mathrm{~m}}=\frac{0.01}{0.52 \times 0.01}=1.92$
Hence, the correct answer is option: 'A'.