chemistry colligative properties of solution Flashcards
is a property of solution that is dependent on the ratio between the total number of solute particles to the total number of solvent particles
colligative property
are not dependent on the chemical nature of the solutions components
colligative properties
_ can be linked to several quantities that express the concentration of a solution such as ,,_.
colligative properties. molarity, normality, molality
four colligative properties that can be exhibited by a solution
boiling point elevation, freezing point depression, relative lowering of vapour pressure, osmotic pressure
the word _ has been adapted or taken from the latin word _ which translates to _
colligative. colligatus. bound together
help us understand how the properties of the solution are linked to the concentration of solute in the solution
colligative properties
containing non volatile solute exhibit some properties which depend only on the number of solute particles present and not on the type of solute present
dilute solution
are changed by the solute where its particles remove some of the solvent molecules in the liquid phase
solvent properties
is dependent on the ratio of solute to solvent molecules in a solution
vapor pressure of electrolyte solutions
a simple example of an electrolyte solution is
sodium chloride in water
are those in which the solute does not dissociate into ions when dissolved
nonelectrolyte solutions
is the pressure exerted by a vapor in equilibrium with its condensed phase
vapor pressure
it is a measure of how much the solvent molecules tend to escape from a liquid or solid phase into the atmosphere
vapor pressure
the number of dissolved particles is larger because the solute breaks apart into ions
electrolyte solution
the entire surface is occupied by the molecules of the solvent
pure solvent
is the vapour pressure of pure solvent
P₀
is the vapour pressure of the solution
Ps
the difference Po - Ps is termed as
lowering in vapour pressure
the ratio Po - Ps / Po is known as the
relative lowering of vapour pressure
established a relation between relative lowering in vapour pressure and mole fraction
Raoult in 1886
it states that the relative lowering in vapour pressure of a dilute solution is equal to the mole fraction of the solute present in the solution
Raoult’s Law
the difference in the boiling point of the solution and the boiling point of the pure solvent is termed as the
elevation in boiling point
is the temperature at which the vapour pressure is equal to atmospheric pressure
boiling point of a liquid`
kb=
molal elevation constant
m₂=
mass of solvent in g
M₁=
mass of solvent in kg
M₂=
molar mass of solute
is defined as the temperature at which the vapour pressure of its liquid is equal to the vapour of the corresponding solid
freezing point of a substance
according to _, when a non volile solid is added to the solvent its vapour pressure decreases
Raoult’s Law
the difference between the freezing point of the pure solvent and its solution is called
depression in freezing point
is the boiling point of the pure solvent
T⁰f
is the boiling point of the solution
Tf
kf=
molal depression constant
is placed between a solution and solvent
semipermeable membrane
allows only solvent molecules to pass through it but prevents the passage of bigger molecules
semipermeable membrane
This phenomenon of the spontaneous flow of solvent molecules through a semipermeable membrane from a pure solvent to a solution or from a dilute to a concentrated solution is called
osmosis
This pressure that just stops the flow of solvent is called
osmotic pressure of the solution.
is a colligative property as it depends on the number of solute present and not on the nature of the solute.
Osmotic pressure
is the gas constant.
R
is the volume of solution in litres
V
osmotic pressure _ is directly proportional to molarity _ and temperature _.
TT, C, T
Two solutions having the same osmotic pressure at a given temperature are known as an .
isotonic solution
has a lower osmotic pressure than that of the surrounding ie, the concentration of solute particles is less than that of the surrounding.
hypotonic solution
has a higher osmotic pressure than that of the surrounding i.e, the concentration of solute particles is more than that of the surrounding.
hypertonic solution
method has the advantage over other methods as pressure measurement is around room temperature. It is particularly useful for determination of the molar mass of biomolecules as they are unstable at higher temperatures.
Osmotic pressure
It is particularly useful for determination of the molar mass of biomolecules as they are unstable at higher temperatures.
Osmotic pressure
The extent of dissociation or association of the solute in a solution can be expressed by a factor called
Van’t Hoff.
is a homogeneous mixture created by dissolving one or more solutes in a solvent.
solution
Solutions with accurately known concentrations can be referred to as
standard (stock) solutions.
are frequently diluted to solutions of lesser concentration for experimental use in the laboratory.
Stock solutions
volumetric flask (commonly called a “).
vol flask”
More solvent is added until the meniscus of the liquid reaches the calibration mark on the neck of the vol flask (a process called “”).
diluting to volume
is the addition of more solvent to produce a solution of reduced concentration.
Dilution
never add _ to concentrated acid
water
different solutions
isotonic solution, hypotonic solution, hypertonic solution
