PCl5(g) → PCl3(g) + Cl2(g)
80% 20% 20%
Assuming the pressure is 1 atm.
The density of the mixture will have an 80% contribution from PCl5
20% contribution from PCl3 and 20% contribution from Cl2
Density of PCl5 at 250C = (208 g/mol /22.4L) x 273K /523K x 0.80 = 3.87 g/L
Density of PCl3 at 250C = (137 g/mol /22.4L) x 273K /523K x 0.20 = 0.63 g/L
Density of Cl2 at 250C = (70.9 g/mol /22.4 L) x 273K /523K x 0.20 = 0.33 g/L
Density of mixture = 3.87 + 0.63 + 0.33 = 4.83 g/L.
