KVPY SA Exam 2018 Question Paper

The maximum amount of nitrogen that can be safely put in this container must, exert a pressure less than 2 atom at 298K.
i.e. maximum moles in container $\mathit{n}=\frac{\mathit{P}\mathit{V}}{\mathit{R}\mathit{T}}$
$=\frac{2\times 2.24}{0.0821\times 298}=0.18$
i. e. maximum weight of N2 in container = 0.183 × 28 = 5.127 gm.
The correct answer is, (D) 4.2 grams
for safety concern, we can’t go for adding more nitrogen.