D. R. Douslin

The Vapor Pressure and Critical Constants of Neopentane

The vapor pressure of neopentane has been measured from 50° to the critical point. The equation, log10p(atmos)=3.901633−1136.462T+4.99118×10−4T  (T=t∘C+273.16), gives a fair representation of the observations.A study of the compressibility of neopentane in the critical region gives for the critical temperature, pressure, volume, and density the values: tc = 160.60°±0.05°C (Int.), pc = 31.57±0.03 normal atmospheres, Vc = 0.303 liter per mole (4.20 ml per g), dc = 3.30 mole/liter (0.238 g per ml). The uncertainty in the critical volume and density is 1 percent.