How is boiling point defined?

The `"boiling point"` is the temperature at which the vapour pressure of the liquid is equal to the ambient pressure and bubbles of vapour form directly in the solution. The `"normal boiling point"` is specified when the ambient pressure is `1*atm`. And thus when we boil the kettle for tea or coffee the vapour pressure of the steam is `1*atm`.

Note that this definition covers vacuum distillation, in that the here the ambient pressure is reduced substantially, and as a consequence the boiling point is also substantially reduced....

The boiling point is the temperature at which the vapor pressure of the liquid is equal to the ambient pressure and bubbles of vapor form directly in the solution.

The normal boiling point
is specified when the ambient pressure is
1⋅atm. And thus when we boil the kettle for tea or coffee the vapor pressure of the steam is 1⋅atm.

Note that this definition covers vacuum distillation, in that the here the ambient pressure is reduced substantially, and the boiling point is also substantially reduced...