Chapter 12 Flashcards
what does solubility mean?
the amount of substance that will dissolve in a given amount of solvent
what does entropy mean?
a measure of energy randomization or energy dispersal
what does miscible mean?
the ability of two or more substances to be soluble in each other in all proportions
what are solvent-solute interactions?
the interactions between a solvent particle and a solute particle
- solvent-solute interaction > solute-solute solvent-solvent interaction SOLUTION FORMS
- solvent-solute interaction = solute-solute, solvent-solvent interaction SOLUTION FORMS
- solvent-solute interaction
what are solvent-solvent interactions?
the interactions between a solvent particle and another solvent particle
what are solute-solute interactions?
the interactions between a solute particle and another solute particle
what is a dynamic equilibrium?
the point at which the rate of reverse reaction is equal to the rate of the forward reaction
what is a saturated solution?
a solution in which the dissolved solute is in dynamic equilibrium with any undissolved solute; any added solute will not dissolve
what is an unsaturated solution?
a solution containing less than the equilibrium amount of solute; any added solute will dissolve until equilibrium is reached
what is a super saturated solution?
an unstable solution in which more than the equilibrium amount of solute is dissolved
what is recrystallization?
a technique used to purify solids in which the solid is put into hot solvent until the solution is saturated; when the solution cools, the purified solute comes out of the solution
what is Henry’s Law?
an equation that expresses the relationship between pressure and the solubility of a gas
Sgas = kH*Pgas Sgas = solubility of gas in mol/L kH = the constant of proportionality Pgas = the partial pressure of the gas
what is molarity (M)?
the amount of solute in moles divided by the volume of the solution in litres
M = amount solute (mol) / volume solution (L)
what is molality (m)?
the amount of solute in moles divided by the mass of the solvent in kilograms
m = amount solute (mol) / mass solvent (kg)
what is parts-by-mass?
the ratio of the mass of the solute to the mass of the solution, all multiplied by a multiplication factor
(mass solute / mass of solution)*multiplication factor
what is parts-per-million?
parts-by-mass multiplied by a multiplication factor of 10^6
what is parts-per-billion?
parts-by-mass multiplied by a multiplication factor of 10^9
what is parts-by-volume?
the ratio of the volume of the solute to the volume of the solution, all multiplied by a multiplication factor
what is a mole fraction?
the amount of of solute in moles divided by the total amount of solute and solvent in moles
Xsolute = amount solute (mol) / total amount of solute and solvent (mol)
what is mole percent?
it is simply mole fraction multiplied by 100%
what is colligative property?
a property that depends on the amount of solute but not on the type
what is Raoult’s Law?
The larger the solvent the larger the vapour pressure of the solution
An equation used to determine the vapour pressure of a solution
Psolution = Xsolvent*Psolvent Psolution = vapour pressure of the solution Xsolvent = mole fraction of solvent Psolvent = the vapour pressure of the pure solvent
define vapour pressure lowering?
the difference in vapour pressure between a pure solvent and a solution of the solvent
ΔP = Psolvent - Psolution ΔP = Xsolute*Psolvent
what is an ideal solution?
a solution that follows Raoult’s Law at all concentrations for both solute and solvent
what is freezing point depression?
The effect of a solute that causes a solution to have a lower melting point than the pure solvent
ΔTf = m*Kf ΔTf = the change in temperature or the freezing point m = the molality of the solution (mol/kg) Kf = is the freezing point depression constant for the solvent
what is boiling point elevation?
the effect of s solute that causes a solution to have a higher boiling point than the pure solvent
ΔTb = m*Kb ΔTb = the change in temperature of the boiling point m = the molality of the solution (mol/kg) Kb = the boiling point elevation constant for the solvent
what is the freezing point depression constant for water?
Kf = 1.86 Celsius/molality
what is the boiling point elevation constant for water?
Kb = 0.512 Celsius/molality
what is osmotic pressure?
The pressure required to stop osmotic flow
Π =MRT
M = molarity of the solution
T = is the temperature in kelvin K)
R = the ideal constant 0.08314barL/molK
what is osmosis?
the flow of solvent from a solution of lower solute concentration to one of higher solute concentration
what is the van’t Hoff factor (i)?
the ratio of particles in a solution to moles of formula units dissolved
i = moles of particles in solution / moles of formula units dissolved
van’t Hoff’s corrections are applied to?
applied to the to freezing point depression, boiling point elevation and osmotic pressure determinations of IONIC solutions
ΔTf =imKf
ΔTb=imKb
Π =iMRT
what is a colloid (colloidal dispersion)?
a mixture in which a dispersed substance is finely divided but not truly dissolved in a dispersing medium
what is the Tyndall effect?
the scattering of light by a colloidal dispersion
