Answer :
number of moles of gas = PV / RT = 0.860 x 2.55 / 0.821 x (22+273)
= 0.009054687 moles
Molar mass of N2 = 28g so we have 0.009054687 moles x 28g / mol = 0.253 g of N2
= 0.009054687 moles
Molar mass of N2 = 28g so we have 0.009054687 moles x 28g / mol = 0.253 g of N2