Question

$Fourgrams$ of copper chloride on analysis was found to contain $1.890g$ of copper ($Cu$) and $2.110g$ of chlorine ($Cl$). What is the empirical formula of copper chloride?

Answer 1

Mass of copper in copper chloride $=1.89g$ (given)

Mass of Chlorine in Copper Chloride $=2.11g$

% age of Cu in $4g$ of copper chloride $=\frac{1.89}{4}\times 100=47.25$%

% age of Cl in $4g$ of copper chloride $=\frac{2.11}{4}\times 100=52.75$%

$\therefore$ In $100g$ of sample:

Mass of $Cu=47.25g$

Mass of $Cl=52.75g$

Moles of $Cu=\frac{47.25}{63.5}=0.74$

Moles of $Cl=\frac{52.75}{35.5}=1.48$

So, ratio of moles of $Cu$ and $Cl$ $=\frac{0.74}{1.48}=\frac{1}{2}$

Thus, the empirical formula of the compound is $CuC{l}_2$