[ $\mathrm{AB}_2$ નું મોલર દળ $=200 \mathrm{~g} \mathrm{~mol}{ }^{-1}$, પાણીનું ઉત્કલનબિંદુ $=100^{\circ} \mathrm{C}, \mathrm{K}_{\mathrm{b}}$ (પાણીનો મોલલ ઉત્કલનબિંદુ ઉન્નયન અચળાંક $\left.=0.52 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}\right)$ ]
\(\mathrm{i}=1+(3-1) \alpha\)
\(\mathrm{i}=1+2 \alpha\)
\(\Delta \mathrm{T}_{\mathrm{b}}=\mathrm{k}_{\mathrm{b}} \mathrm{im}\)
\(0.52=0.52(1+2 \alpha) \frac{\frac{10}{200}}{\frac{100}{1000}}\)
\(1=(1+2 \alpha) \frac{10}{20}\)
\(2=1+2 \alpha\)
\(\alpha=0.5\)
Ans. \(\alpha=5 \times 10^{-1}\)
(પાણી માટે $K_f = 1.86\,^oC\, kg\, mol^{-1}$ છે)
(મોલર દળ $S = 32\, g\, mol^{-1}, Na = 23\, g\, mol^{-1}$ )