Question

The maximum number of molecules are present in :-

• A. $5L\text{of}{N}_2\text{gas at}STP$
• B. $0.5g\text{of}{H}_2\text{gas}$
• C. $10g\text{of}{O}_2\text{gas}$
• D. $15L\text{of}{H}_2\text{gas at}STP$

Answer 1

The correct option is D $15L\text{of}{H}_2\text{gas at}STP$

As we know, 1 mole of a gas has $N_A$ molecules. So, higher the number of moles of a gas, higher will be the number of molecules.

$\left(a\right)$ $\text{Mole of}{N}_2=\frac{5}{22.4}=0.22mol$

$\left(b\right)$ $\text{Mole of}{H}_2=\frac{0.5}{2}=0.25mol$

$\left(c\right)$ $\text{Mole of}{O}_2=\frac{10}{32}=0.31mol$

$\left(d\right)$ $\text{Mole of}{H}_2=\frac{15}{22.4}=0.67mol$

So, $0.67$ mole of $H_2$ will have the highest number of molecules.

Hence the correct option is (d).