Question

A compound contains 3.2% of oxygen. The minimum molecular weight of the compound is:

• A. 300 u
• B. 440 u
• C. 350 u
• D. 500 u

Answer 1

Answer: (D)

500 u

The minimum number of oxygen atoms the compound can contain is $1.$

Atomic weight of oxygen= $16u$

If 3.2 % of the compound weighs $16u$

Then 100 % of the compound will weigh = $\left(\frac{100}{3.2}\right)\times 16=500u$

$\therefore$ Minimum molecular weight of the compound = $500u$