Question

An oxide of a metal (M) contains $40 \%$ by mass of oxygen. Metal (M) has atomic mass of 24. The empirical formula of the oxide is-

• A. $M _{2} O$
• B. $MO$
• C. $M _{2} O _{3}$
• D. $M _{3} O _{4}$

Answer 1

Answer: (B)

$40\, gm\, O$ present in $100 g$ metal oxide

$16 g ---\frac{100}{40} \times 16=40 g$

mol wt of metal oxide $=40\, g$

At wt of metal $=24\, g$

wt of oxygen $=16 \,g$

$\therefore$ Hence formula $= MO$