Question

How many number of molecules and atoms respectively are present in $2.8$ litres of a diatomic gas at $STP$?

• A. $6.023\times 10^{23},7.5\times 10^{23}$
• B. $6.023\times 10^{23},15\times 10^{22}$
• C. $7.5\times 10^{22},15\times 10^{22}$
• D. $15\times 10^{22},7.5\times 10^{23}$

Answer 1

Answer: (C)

Number of molecules of gas at $STP$
$=\frac{6.023\times 10^{23}\times 2.8}{22.4}$
$=7.5\times 10^{22}$ Molecules
Number of atoms in diatomic molecule
$=2\times 7.5\times 10^{22}=15\times 10^{22}$ atoms