Ch 13 | Ions in Aqueous Solutions and Colligative Properties

dissociation

separation of ions that occurs when an ionic compound dissolves

net ionic equation

Includes only those compounds and ions that undergo a chemical change in a reaction in an aqueous solution

spectator ions

Ions that do not take part in a chemical reaction and are found in solution both before and after the reaction

ionization

process in which ions are formed from solute molecules by the action of solvent; molecular/nonpolar in polar

dissociation vs ionization

dissociation starts with an ionic compound and ionization starts with a molecular compound

hydronium ion

hydrogen ion attracts other ions/molecule so strongly that is doesn't normally exist alone > bonds with a water molecule to form

electrolyte's strength depends on

how many dissolved ions it contains; related to their ability to form ions in solutions

strong electrolyte

any compound whose dilute aqueous solutions conduct electricity well; this is due to the presence of all or almost all of the dissolved compound in the form of ions

strong electrolyte examples

all soluble ionic compounds and HCl, HBr, HI, H2SO4, HNO3, HClO4, HClO3

weak electrolyte

any compound whose dilute aqueous solutions conduct electricity poorly; this is due to the presence of a small amount of the dissolved compound in the form of ions

colligative property

depends on the concentration of solute particles but not on the identity

freezing point depression

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

determining actual freezing point (solvent is water)

negative of ΔTf

determining actual freezing point (solvent is not water)

Tf (solvent) - ΔTf

boiling-point elevation

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

determining actual boiling point

Tb (solvent) + ΔTb

when solute is ionic/polar

multiply ΔT by # of solute ions