If the pressure on the liquid differs from one atmosphere, the boiling point observed for the compound differs from that estimated for the pure compound. Thermally unstable compounds can not measure its boiling point. At that time, we apply reduced pressure distillation.

Have you ever seen chart above? If you set ruler one certain pressure and normal boiling point then you can get boiling point at certain pressure. Or you set ruler one certain pressure and boiling point at that pressure, you can get normal boiling point. This JAVA applet calculate these converted value.

Related Properties Vapor Pressure , Vapor Pressure and Boiling Point.