Question

If 224 ml of a triatomic gas has a mass of 1 g at 273 K and 1 atm pressure, then the mass of one atom is:

• A. $8.30\times {10}^{-23}gm$
• B. $2.08\times {10}^{-23}gm$
• C. $5.53\times {10}^{-23}gm$
• D. $6.24\times {10}^{-23}gm$

Answer 1

The correct option is C $5.53\times {10}^{-23}gm$

Using ideal gas law equation,

$PV=nRT$

$V=224ml=0.224L$, $P=1atm$, $R=0.082$ and $T=273K$

$1atm\times 0.224L=n\times 0.082Latm{mol}^{-1}{K}^{-1}\times 273K$

$n=0.01mol$

0.01 mol of gas contains 1g.

1mol of gas $=100g$

Therefore, $6.022\times {10}^{23}\times 3atoms=100g$

Mass of one atom $=5.53\times {10}^{-23}g$