Question

A sample of oxygen gas (O2) has a temperature of 273 K at 1.00 atm. What should the density of this gas be? Show all of the work used to find your answer.

Answer 1

According to Ideal Gas Equation,

                                      P V  =  n R T
Also,
                                          n  =  mass / M.mass
So,
                                      P V  =  (mass × R × T) ÷ M.mass
Or,
                         P × M.mass  =  (mass × R × T) ÷ V
Since,
                       Density = mass / volume
So,
                                           P × M.mass  =  Density × R × T
Or,
                              Density  =  (P × M.mass) ÷ (R × T)
Putting Values,

   Density  =  (1.0 atm × 32 g/mol) ÷ (0.0821 L.atm.mole⁻¹.K⁻¹ × 273 K)

                                           Density  = 1.42 g/L