Question

7.5 grams of a gas occupies 5.6 litres of volume at $STP$. The gas is (atomic weights of $C$,$N$ and $O$ are 12, 14 and 16 respectively) :

• A. $NO$
• B. $N_{2}O$
• C. $CO$
• D. $C{O}_2$

Answer 1

The correct option is A $NO$

One mole of gas at $STP$ occupies 22.4 liters.
Thus, 5.6 litres of gas at $STP$ contains 0.25 moles

$no.ofmoles=\frac{wt.ingrams}{Mol.wt.}$

$0.25=\frac{7.5}{M}$

$M$ = 30

Thus, the gas is $NO$