Question

$0.76g$ of a silver salt of a dibasic acid on ignition gave $0.54g$ of silver. Calculate the molecular mass of the acid.

Answer 1

Wt of $Ag$ salt $=0.76$gm

Wt of $Ag$ after ignition $=0.54$gm

$\frac{Eq.wt.ofsilversalt\left(E\right)}{Eq.wt.ofAg}=\frac{wt.ofsilversalt}{wt.ofAg}$

$\Rightarrow \frac{E}{108}=\frac{0.76}{0.54}\Rightarrow E=152$

Eq. wt. of acid $=$ (Eq. wt. of silver salt) $-$ (Eq. wt. of $Ag$) $+\frac{Basicity}{2}$

$=152-108+1=45$

$\therefore$ Molar mass of acid $=45\times 2=90$gm ${mole}^{-1}$