The observed and calculated molecular weights | vedclass

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(C) The van't Hoff factor $i$ is given by the ratio of the calculated molecular weight to the observed molecular weight.$i = \frac{	ext{Calculated mo

Vedclass · Accepted Answer

$75$

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(C) The van't Hoff factor $i$ is given by the ratio of the calculated molecular weight to the observed molecular weight.$i = \frac{	ext{Calculated molecular weight}}{	ext{Observed molecular weight}} = \frac{164}{65.6} = 2.5$For the dissociation of calcium nitrate: $Ca(NO_3)_2 ightarrow Ca^{2+} + 2NO_3^-$,the number of ions produced per formula unit is $n = 3$.The relationship between the van't Hoff factor and the degree of dissociation $\alpha$ is $i = 1 + (n - 1)\alpha$.Substituting the values: $2.5 = 1 + (3 - 1)\alpha$$2.5 = 1 + 2\alpha$$1.5 = 2\alpha$$\alpha = 0.75$Therefore,the degree of dissociation in percentage is $\alpha 	imes 100 = 75\%$.

The observed and calculated molecular weights of calcium nitrate are $65.6$ and $164$ respectively. The degree of dissociation of calcium nitrate is .......... $\%$.

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