Question

If atomic eq. 40% of $PC{l}_5$ dissociated. Calculate equivalent molar mass.

Answer 1

$PC{l}_5\left(g\right)\rightleftharpoons PC{l}_3\left(g\right)+C{l}_2\left(g\right)$

Lct ni(initial moles of $PC{l}_5)=1$

ni $1$ $0$ $0$

neq $1-0.4=0.6$ $0.4$ $0,.4$

$\therefore$ molar mass =$\sum$ mols tradition of complement $\times$ molecules mass

$=\frac{0.4}{1.4}\times 71+\frac{0.4}{1.4}\times 137.5+\frac{0.6}{1.4}\times 208.5$

$=148.93$