Molecular weight of N2
gram Atomic weight of N is 14 g.
gram Molecular weight = 14 g×2
= 28 g
Liter concepts
1 liter of gas always occupies 1 gram molecular weight .
Application of the concept
5.75 liter gives 0.257g
1 mole will occupy 28 g
0.257 will occupy 28 g × 0.257
= 7.196 g
The mass of the gas is 7.196 g.
Hope it helps you