Normal molar mass of MX2=164.0 g mol−1 Observed molar mass of MX2=65.6 g mol−1 $\begin{aligned}
& \text { Van't Hoff factor }(\mathrm{i})=\frac{\text { Normal molar mass }}{\text { Observed molar mass }} \
& =\frac{164}{65.6}=2.5
\end{aligned}If\alphaisthedegreeofionisation,then\begin{aligned}
& \underset{1-\alpha}{\mathrm{MX}2} \rightleftharpoons \mathrm{M}\alpha^{2+}+\underset{2 \alpha}{2 \mathrm{X}^{-}} \
& \mathrm{i}=1-\alpha+\alpha+2 \alpha=1+2 \alpha \
& 1+2 \alpha=2.5 \
& \alpha=0.75
\end{aligned}\thereforePercentdegreeofionisation=75 %$
The observed and normal molar masses of compound MX_2 are 65.6 and 164 respectively. The percent degree of ionisation of MX_2 is … %. (Nearest…
JEE Main 2025 — Chemistry Physical Chemistry
The observed and normal molar masses of compound MX2 are 65.6 and 164 respectively. The percent degree of ionisation of MX2 is …… %. (Nearest integer)
Held on 24 Jan 2025 · Verified 6 Jul 2026.
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