Page 180 - Chemistry eBook
P. 180
Phase Changes in Liquids
VAPORIZATION: Liquid changes to gas
• VAPOR PRESSURE: The pressure the vapor molecules apply
When the temperature rises, the
vapor pressure rises.
When the temperature decreases,
the vapor pressure decreases.
Hot coffee (liquid) changing to steam (gas)
Now let’s ask Reffy to
help us figure out vapor pressure and atmospheric pressure so that we can find the boiling point of a substance.
• BOILING occurs when the vapor pressure is equal to the atmospheric pressure.
(When the temperature of the liquid rises, the vapor pressure rises until the vapor pressure becomes equal to the atmospheric pressure.)
179 © UNIT 5: MATTER
