Solutions and Colligative Properties - Result Question 23-1
23. The freezing point of equimolal aqueous solutions will be highest for
(1990, 1M)
(a) $\mathrm{C}_6 \mathrm{H}_5 \mathrm{NH}_3 \mathrm{Cl}$ (aniline hydrochloride)
(b) $\mathrm{Ca}\left(\mathrm{NO}_3\right)_2$
(c) $\mathrm{La}\left(\mathrm{NO}_3\right)_3$
(d) $\mathrm{C}6 \mathrm{H}{12} \mathrm{O}_6$ (glucose)
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Answer:
Correct Answer: 23. (d)
Solution:
$ \begin{array}{lr} \mathrm{C}_6 \mathrm{H}_5 \mathrm{NH}_3 \mathrm{Cl}: & i=2 ; \\ \mathrm{Ca}\left(\mathrm{NO}_3\right)_2: & i=3 \\ \mathrm{La}\left(\mathrm{NO}_3\right)_3: & i=4 ; \\ \mathrm{C}6 \mathrm{H}{12} \mathrm{O}_6: & i=1 \end{array} $
Lower the value of i, smaller will be the depression in freezing point, higher will be the freezing temperature, if molalities are equal. Hence, glucose solution will have highest freezing temperature.
BETA
