What is the relation between the normal boiling point and the vapour pressure of liquids?and why?

1 Answer
Apr 14, 2018

Well, the #"normal boiling point...."#

Explanation:

#"The normal boiling point"# is the temperature at which the vapour pressure of a liquid is EQUAL to ONE ATMOSPHERE. And so at the normal boiling point the vapour pressure of the boiling liquid is equal to the ambient pressure, and bubbles of vapour form directly in the liquid.

And you will appreciate this is the principle behind vacuum distillation. If the ambient pressure is reduced under high vacuum, an otherwise involatile liquid may be distilled, i.e. boiled, in that its vapour pressure becomes equal to the ambient pressure.