Question

Calculate the density of oxygen, O2, under each of the following conditions:
STP
1.00 atm
and 25.0 ∘C

Answer 1

Molicular weight of O_2, M= 32 g/mol

We know that, STP = standard temperature and pressure.

i.e. At 1 atm pressure and 25°C

At STP 1 mole of O2 occupies the volume , V = 22.4 L/mol

Hence density, ρ_STP = (mass/volume)

=(M g/mol)/(V L/mol)

= (32/22.4)g/L

= 1.428 g/L

(upto three significant decimal place)

Hence, the density of O₂ at STP =1.428 g/L.