Chemistry - Solutions

Solutions

Solutions

Homogeneous mixtures made up of very small particles; molecules, atoms, or ions

Three groups of solutions

Solids, liquids, and gas

Solid solution

Solution in a solid phase, solid is solvent

Liquid

Solution in liquid phase, liquid is solvent

Gas

Solution in gas phase, gas is solvent

Solubility

Amount of solute that will dissolve under given conditions

Saturated

As much solute as possible

Unsaturated

Room for more

Supersaturated

More than you can have

Precipitate

Extra solute that falls out

Dilute

Small amount of solute

Concentrated

Large amounts of solute

Factors that affect solubility

Pressure & nature of solute and solvent

Factors that affect the rate of solubility

Particle size, stirring, amount of solute already present, temperature

Solubility Curve: on the line

Saturated

Solubility Curve: under line

Unsaturated

Solubility Curve: over line

Supersaturated

Solvation Process

Process by which a solute becomes surrounded by a solvent; anything that dissolves becomes solvated

Solvation

Molecule surrounded by solvent

Ionization

Compound dissociates, charges, and surrounded by water

Electrolytes

A compound that conducts electric current when it is in an aqueous solution or in the molten state

Nonelectrolytes

A compound that does not conduct an electric current in either aqueous solution or the molten state

Strong acids

HI, H2SO4, HBR, HCl, HClO4, HNO3

Strong bases

LiOH, NaOH, KOH, RbOH, CsOH, Ca(OH)2, Sr(OH)2, Ba(OH)2

Colligative Properties

Property that depends on the number of solute particles but is independent of their nature

Nonvolatile solute

Little tendency to become a gas under existing conditions, typically a solid

Vapor-pressure lowers if…

… something is in the way of the water evaporating

Molality

The concentration of a solution expressed in moles of solute per kilogram of solvent; # of moles of solute

Freezing Point Depression

The difference in temperature between the freezing point of a solution & the freezing point of pure solvent

Boiling Point Elevation

The difference in temperature between the boiling point of a solution & the boiling point of pure solvent

Molarity

The numbers of moles of solute in one liter of solution

Percent by Mass

Number of grams of solute dissolved in 100 grams of solution