Question

How many atoms are present in $179.2L$ of a $N_2$ gas at STP?

• A. $4.82\times {10}^{24}$
• B. $2.41\times {10}^{24}$
• C. $9.63\times {10}^{23}$
• D. $9.63\times {10}^{24}$

Answer 1

The correct option is D $9.63\times {10}^{24}$

At STP, volume of $1$ mole of gas $=22.4L$

So, no. of moles of $N_2$ gas $=\frac{179.2}{22.4}=8$ moles

No. of molecules of $N_2=8\times 6.023\times {10}^{23}$

No. of atoms $=2\times [8\times 6.023\times {10}^{23}]=9.63\times {10}^{24}$