What is vapor pressure?
The equilibrium vapour pressure is typically the pressure exerted by a liquid .... it is A FUNCTION of temperature...
By way of example, chemists and physicists habitually use
Well, because this is the normal boiling point of water: i.e. the conditions of pressure (i.e. here
At lower temperatures, water exerts a much lower vapour pressure...but these should often be used in calculations...especially when a gas is collected by water displacement. Tables of