Question

A pure sample of cobalt chloride weighing $1.30$ g was found to contain $0.59$ g cobalt and $0.71$ g chloride on quantitative analysis. If the percentage composition of cobalt $=x\%$ and chloride $=y\%$, then the value of $x$ and $y$ are, respectively:

• A. $45.4,54.6$
• B. $40.2,60.4$
• C. $50.0,50.2$
• D. none of the above

Answer 1

The correct option is A $45.4,54.6$

$1.30$ g of the compound $=0.59$ g of $Co$
$100$ g of the compound $=\frac{0.59\times 100}{1.3}=45.4\%$
$1.30$ g of the compound $=0.71$ g of chloride
$100$ g of the compound $=\frac{0.71\times 100}{1.3}=54.6\%$

Hence, the value of $x$ and $y$ are $45.4$ and $54.6$ respectively.