Section 13 Flashcards
Define: dissociation
The separation of ions that occurs when an ionic compound dissolves.
What is a net ionic equation?
A net ionic equation includes only those compounds and ions that undergo a chemical change in a reaction in an aqueous solution.
What is a spectator ion?
Ions that do not take part in a chemical reaction and are found in solution both before and after the reaction.
What is “ionization” and what does the extent to which ionization occurs depend on?
Ionization- Ions are formed from solute molecules by the action of the solvent in this process. In general, the extent to which a solute ionized in solution depends on the strength of the bonds within the molecules of the solute and the strength of attraction between the solute and solvent molecules.
Define: Strong electrolyte
A Strong Electrolyte conducts electrivity well because most of the compound dissolves into ions when dissolved.
Define: Weake electrolyte
A weak electrolyte does not conduct electricity well because some of the compound does not dissociate into ions when dissolved.
Define: colligative properties
Properties that depend on the concentration of solute particles but not on their identity.
Why are boiling point and freezing point of a solution different from those of the pure solvent?
Dissolution of a substance decreases the water vapor pressure over the solution. In sense, the solute molecules “get in the way” of the water that is trying to escape, thus more energy is required to vaporize the substance (ie. boiling point increases)
Define: Freezing Point Depression
tf, the difference between the freezing points of the pure solvent and a solution of a nonelectrolyte in that solvent, and it is directly proportional to the molal concentration of the solution.
Define: Molal Freezing Point Constant
(Kf) is the free point depression of the solvent in a 1-molal solution of a nonvolatile, nonelectrolyte solute.
(-1.86degrees if added water per mole)
Define: Boiling Point Elevation
tb, is the difference between the boiling points of the pure solvent and a nonelectrolyte solution of that solvent, and it is directly proportional to the molal concentration of the solution.
Define: Molal Boiling Point Constant
(Kb) is the boiling-point elevation of the solvent in a 1-molal solution of a nonvolatile, nonelectrolyte solute.
(+,51degrees if added water per mole)
Define: Semipermeable membrane
It allows the passage of some partibles while blocking the passage of others
Define: Osmosis
The movement of solvent through a semipermeable membrane from the side of lower solute concentration to the side of high solute concentration
Define: Osmotic Pressure
The external pressure that must be applied to stop osmosis.
