10.4

Phase – any part of a system with uniform composition and properties.

Condensation – gas changes to a liquid

Molecules of liquid can evaporate and then condense and re-enter the liquid phase

Condensation and evaporation can happen at the same rate…

Equilibrium – a dynamic condition in which 2 opposing changes occur at equal rates in a closed system

No net change in amt. of substance in either phase.

P is directly proportional to [ ]Equilibrium vapor pressure – pressure exerted by vapor in equilibrium with its corresponding liquid at a given temp

Different for each liquidThe higher the bonding the _____the EVP

Think about the KMT

Volatile Liquids – liquids that evaporate readily

__________ forces of attraction.Boiling – conversion of a liquid to a vapor within the liquid as well as at the surface

Boiling point – the temp at which the equilibrium vapor pressure of the liquid = atm pressure

The ________ the atm pressure, the lower the b.p.

Temp is constant while boilingNormal atmospheric pressure = 1 atm, 760 torr, 101.325kPa

E needs to be + constantly to continue boiling

MEV – the amt of E as heat that is needed to vaporize 1 mol of liquid at the liquids b.p. at constant pressure.

ΔHv Measure of attraction of particles

Freezing – physical change of liquid to solid

Loss of EFreezing point – the temp at which solid and liquid are at equilibrium at 1 atm

At f. p. particles have same amt of ave K. E.

At m.p. the solid and liquid have the same amt of k.e. also.

For pure crystalline solids, f.p. and m.p. are at the same temp.

Molar Enthalpy of fusion – the amount of energy as heat required to melt one mole of solid at the solids melting point.