Chapter 13- Solutions and Colligative Properties

Chapter 13- Solutions and Colligative PropertiesColligative Properties

Colligative Properties - depend on the concentration of the solution, not on the type of particle dissolved.

Vapor Pressure of Solutions: Vapor pressure decreases as concentration increases.

Raoult's Law: Psoln = XsolventPsolvent

ideal solutions obey Raoult's LawAnimation

Boiling Point Elevation: boiling point increases as concentration increases.Tb = Kb mmolal boiling point constantTable 13.4 p. 549Freezing Point Depression: freezing point decreases as concentration increases.Tf = Kf m

molal freezing point constantTable 13.4 p.549

Osmosis: net movement of solvent toward the more concentrated solution through a semipermeable membrane. The minimum pressure that stops osmosis is the osmotic pressure.

= MRT

Electrolyte SolutionsFor a 1 molal water solution we would expect Tf to be -1.86 C but for NaCl it is twice that because NaCl dissociates into Na+ and Cl- which is twice as many particles.van't Hoff Factor, i = moles of particles in solution moles of solute dissolved

Usually colligative effects for an electrolyte are a little less than predicted due to solute-solute and solute-solvent interactions.T = i K m = i MRT

Colloids - suspension of tiny particles in a medium. Cloudiness of mixture can be observed by eye or by passing light through the mixture (Tyndall Effect)

Notes quizhttps://docs.google.com/spreadsheet/embeddedform?formkey=dExQTG5wdU9nVC12V0VOYklUVk5mM3c6MQ