Question

When 4.215g of metallic carbonate was heated in a hard glass tube, the $C{O}_2$ evolved was found to be measured 1336 mL at 27${}^{\circ }$C and 700mm pressure. If $X$ g is the equivalent weight of the metal, then find the value of $1000X$.

Answer 1

Moles of $C{O}_2$ evolved.

Using $PV=nRT$

$P=\frac{700}{760}=0.921$ $atm$ $V=1.336$ $L$ $T=300$ $K$

$n=\frac{1.336\times 0.921}{300\times 0.0821}=0.05$ $moles$

$MC{O}_3⟶MO+C{O}_3$

$0.05$ $moles$

So, $0.05$ $moles$ of $MC{O}_3$ must have reacted.

Let molecular mass of metal be $W$

$\frac{4.125}{W}=0.05$

$\Rightarrow W=82.5$ $g$

$Equivalentweight=\frac{Molecularweight}{Valency}=\frac{82.5}{2}=41.25$ $g=X$

$\Rightarrow 1000X=41250$