$50$g of a metal when completely reacts with oxygen, mass of metal oxide becomes $75$g. What is the equivalent mass of the metal oxide?

The correct option is A $16$
Weight of metal given= $50g$

Mass of metal oxide= $75gm$

% of metal in metal oxide= $\frac{50}{75}=66.66$%

Equivalent weight= $\frac{\text{Weight of metal}}{\text{Weight of oxygen combined}}\times 8$

$=\frac{66.66}{33.33}\times 8=16$ .