Lecture 2 Flashcards
Define Electrolyte
A compound (any phase) that undergoes dissociation into ions in aqueous solution
Electrolytes can be
Ionic (Ionic bonds)
Molecular (Covalent bonds)
Inorganic
Organic
Combination of both
Strong electrolytes
1) Define
2) Example
1) Dissociate completely, solution contains ions only
2) Inorganic salts, acids, bases
Weak Electrolytes
1) Define
2) Examples
1) Dissociate partially, contains small fractions of ions
2) Organic acids, bases
Non-Electrolytes
1) Define
2) Examples
1) Produces no ions, solution contains whole molecules only
2) Organics
Van’t Hoff Factor
1) Define
2) Denoted by
3) Example
1) Expresses, in moles, the number of ions/particles produced when 1 mole of the substance dissolves
2) i
3) LiCl > Li+ + Cl- =
2 moles of ions produced = i = 2
Van’t Hoff Factor (i) in:
1) Strong electrolytes
2) Nonelectrolytes
3) Weak Electrolytes
1) i = How many ions in solution
2) i = 1
3) i = 1 + a
Define Colligative Properties
Such properties of a solution that depend on the number of solute particles, and do not depend on the identity of solute particles
Colligative effects (4)
1) Vapour pressure
2) Boiling pint elevation
3) Freezing point depression
4) Osmosis
Vapour Pressure
1) Denoted by
2) Define
3) Depends on
4) What happens when equal to outside pressure
1) p^o
2) The pressure exerted by its vapour in thermodynamic equilibrium with the condensed phase
3) Temperature
4) Boiling
What are substances that exhibit
1) High
2) Low
vapour pressures are called
1) Volatile substances
2) Non-Volatile substances
Raoult’s Law
P vapour =
x solvent x P^o solvent
+
x solute x P^o solute
For non-volatile solute =
p^o solute = 0
Boiling Point Elevation
1) Direct consequence of
2) Formula
3) Kb for water (at normal bp)
1) Vapour pressure lowering
2) Delta Tb = i x kb x m(underlined) solute
3) Kb = 0.513 K x kg/mol
