Chemistry - Liquid Solution Question with Solution | TestHub

${\mathrm{K}}_2{\mathrm{SO}}_4$ dissolved $=25\mathrm{mg}=0.025\mathrm{g}$ Volume of solution $=2\mathrm{L}$ Temperature, $T=25^{\circ }\mathrm{C}=298\mathrm{K}$ Molar mass of ${\mathrm{K}}_2{\mathrm{SO}}_4=2\times 39+32+4\times 16$ $=174\mathrm{g}{\mathrm{mol}}^{-1}$ As, ${\mathrm{K}}_2{\mathrm{SO}}_4$ dissolve completely ${\mathrm{K}}_2{\mathrm{SO}}_4⟶2{\mathrm{K}}^{+}+{\mathrm{SO}}_4^{2-}$ i.e. ions produced $\left(1^{\circ }\right)=3$ $\begin{array}{rl}\therefore i& =3\\ \pi & =iCRT=i\frac{n}{V}RT=\frac{i}{M}+\frac{1}{V}\times RT\\ & =3\times \frac{0.025}{174}\times \frac{1}{2}\times 0.0821\times 298\\ \pi & =5.27\times 10^{-3}\mathrm{atm}\end{array}$