Question

A metal oxide contains 60 % of metal by mass. The equivalent weight of the metal is:

• A. $12\text{g}$
• B. $40\text{g}$
• C. $40\text{g}$
• D. $24\text{g}$

Answer 1

The correct option is A $12\text{g}$

Let the weight of metal oxide is $100\text{g}$.
Weight of oxygen = $40\text{g}$; weight of metal = $60\text{g}$
$\frac{\text{weight of metal}}{\text{weight of oxygen}}=\frac{\text{equivalent weight of the metal}}{\text{equivalent weight of oxygen}}$
$\Rightarrow \frac{60}{40}=\frac{M}{8}$
On solving, $M=12\text{g}$