a) Moles of air molecules= PV/RT
                                              Â
=1.00*237*103/0.0821*299
                                              Â
=9.655*103 mol
              Â
Molecules of
air=9.655*103*6.022*1023=5.814*1027
molecule
b) Molecule density= Molecules/ volume in cm3
                                              Â
=5.814*1027/237*106
                                              Â
=2.453*1019 molecule/cm3
c) Mass of air= moles of air*mol wt of N2
                              Â
=9.655*103*28
                              Â
=270.340 kg