• # question_answer A pre-weighed vessel was filled with oxygen at N.T.P. and weighted. It was then evacuated, filled with $S{{O}_{2}}$ at the same temperature and pressure, and again weighted. The weight of oxygen will be        [NCERT 1989] A)                 The same as that of $S{{O}_{2}}$ B)                 $\frac{1}{2}$that of$S{{O}_{2}}$ C)                 Twice that of$S{{O}_{2}}$ D)                 One fourth that of$S{{O}_{2}}$

$\frac{M.\,wt.\,of\,{{O}_{2}}}{M.\,wt.\,of\,S{{O}_{2}}}\Rightarrow \frac{{{M}_{1}}}{{{M}_{2}}}\Rightarrow \frac{32}{64}=\frac{1}{2}$                                 The weight of oxygen will be $\frac{1}{2}$that of $S{{O}_{2}}$