Prediction of vapor pressures of pure compounds from knowledge of the normal boiling point temperature

A simple method for the prediction of vapor pressures of pure compounds from knowledge of the normal boiling point temperature is presented. Typical errors down to 10−5 bar (1 Pa) are below 20% and are off only by a factor of 2–3 down to 10−9 bar (10−4 Pa), which must be considered very satisfactory considering the simplicity of the method and the uncertainty in the very low vapor pressure data. gher pressures, up to 5 bar, very satisfactory results are obtained with typical errors below 3% but somewhat higher for alcohols.