Question

20 g of an ideal gas contains only atoms of S and O occupies 5.6 L at 1 atm and 273 K what is the molecular mass of gas

• A. 64
• B. 80
• C. 96
• D. None of these

Answer 1

The correct option is B 80

Moles = $\frac{Volume\left(atSTP\right)}{22.4}$

Also, moles = $\frac{Weight}{Mol.Mass}$

Thus, $\frac{Volume\left(atSTP\right)}{22.4}$ = $\frac{Weight}{Mol.Mass}$

$\frac{5.6}{22.4}$ = $\frac{20}{x}$

Hence , x = 80, option B is correct