the temperature at which a given substance will change from a liquid into a gas ?

Sagot :

The answer is boiling point.

When a liquid boils, it starts to change into gaseous state. The boiling point of the substance is the temperature at which the liquid starts to boil, i.e change from liquid to gas. 
So, the temperature at which a given substance will change from liquid to gas is the boiling point of that substance.