Question

Assertion : Molecular weight of a compound is $180$, if its vapour density is $90$.
Reason : $\text{Molecular weight}=\frac{\text{Vapour density}}{2}$

• A. If both assertion and reason are true and reason is the correct explaination of assertion
• B. If both assertion and reason are true and reason is not the correct explaination of assertion
• C. If assertion is true but reason is false
• D. If both assertion and reason are false

Answer 1

The correct option is C If assertion is true but reason is false

$\text{Vapour density (V.D.)}=\frac{\text{Molecular weight}}{2}$
$\therefore \text{Molecular weight}=2\times \text{vapour density of gas}$

Hence the correct answer is option (c).