a) Heterogeneous in nature
b) Uniform composition
c) Do not scatter light
d) Can be separated by filtration
Answer: a) Heterogeneous in nature
Explanation: Colloidal solutions are heterogeneous mixtures,
containing particles that are larger than molecules but small enough to stay
dispersed in a solution.
a) Foam
b) Aerosol
c) Emulsion
d) Sol
Answer: a) Foam
Explanation: A foam is a colloidal system in which gas is
dispersed in a liquid.
a) Coagulation
b) Dispersion
c) Redispersion
d) Adsorption
Answer: a) Coagulation
Explanation: Coagulation is the process in which a colloidal
solution is converted into a precipitate, typically by adding electrolytes.
a) Water in oil emulsion
b) Gelatin in water
c) Smoke in air
d) Soap solution
Answer: b) Gelatin in water
Explanation: Lyophilic colloids are "solvent-loving" colloids,
such as gelatin in water, where the dispersion medium is attracted to the
dispersed phase.
a) Transparent solutions
b) Homogeneous mixtures
c) Colloidal solutions
d) Pure liquids
Answer: c) Colloidal solutions
Explanation: The Tyndall effect is the scattering of light by
colloidal particles, which is why colloidal solutions show this effect.
a) Gelatin in water
b) Starch in water
c) Oil in water
d) Smoke in air
Answer: d) Smoke in air
Explanation: Hydrophobic colloids do not have an affinity for
the dispersion medium, like smoke in air.
a) It stabilizes the colloidal particles
b) It causes coagulation of the colloidal particles
c) It makes the colloidal particles dissolve
d) It increases the dispersion medium
Answer: b) It causes coagulation of the colloidal particles
Explanation: The addition of electrolytes to a colloidal
solution can neutralize the charge on the colloidal particles, leading to
coagulation.
a) Absorption
b) Adsorption
c) Solution
d) Sublimation
Answer: b) Adsorption
Explanation: Adsorption refers to the accumulation of molecules
on the surface of a solid or liquid.
a) They are unstable in water
b) They form gels easily
c) They cannot be dispersed in water
d) They are hydrophobic
Answer: b) They form gels easily
Explanation: Hydrophilic colloids are "solvent-loving" and
readily form stable gels when dispersed in water.
a) The adsorbate is uniformly distributed throughout the medium
b) Adsorption increases with an increase in temperature
c) Adsorption is usually an exothermic process
d) Adsorption does not depend on surface area
Answer: c) Adsorption is usually an exothermic process
Explanation: Adsorption is typically an exothermic process,
where energy is released when molecules adhere to a surface.
a) Milk
b) Blood
c) Jelly
d) Smoke
Answer: c) Jelly
Explanation: A gel is a colloidal system where a solid network
is formed in a liquid medium, such as jelly.
a) Sol
b) Emulsion
c) Aerosol
d) Foam
Answer: a) Sol
Explanation: A sol is a colloidal system where solid particles
are dispersed in a liquid medium.
a) They show Brownian motion
b) They are homogeneous mixtures
c) They do not scatter light
d) They can be separated by dialysis
Answer: c) They do not scatter light
Explanation: Colloidal solutions scatter light, a phenomenon
known as the Tyndall effect.
a) 1–100 nm
b) 1–100 µm
c) 0.1–0.5 nm
d) 1–10 cm
Answer: a) 1–100 nm
Explanation: Colloidal particles typically range in size from 1
to 100 nm.
a) Increases continuously
b) Decreases continuously
c) Increases initially, then levels off
d) Remains unaffected
Answer: c) Increases initially, then levels off
Explanation: Initially, adsorption increases with pressure, but
it eventually levels off when the surface becomes saturated.
a) Physical adsorption
b) Chemical adsorption
c) Both a and b
d) None of the above
Answer: b) Chemical adsorption
Explanation: Chemical adsorption involves the formation of
strong chemical bonds between the adsorbate and the surface.
a) High molecular weight of solute
b) Presence of electrical charges on particles
c) Presence of larger particles
d) None of the above
Answer: b) Presence of electrical charges on particles
Explanation: The stability of lyophilic colloids is due to the
presence of electrical charges on the particles, which prevents aggregation.
a) Paint
b) Blood
c) Air
d) Milk
Answer: c) Air
Explanation: Air is a homogeneous mixture, not a colloidal
solution.
a) The concentration at which a solute forms a monolayer on the surface
b) The concentration at which a solute forms a gel
c) The concentration at which micelles form in a solution
d) The concentration at which a solute precipitates from the solution
Answer: c) The concentration at which micelles form in a
solution
Explanation: CMC is the concentration at which surfactant
molecules form micelles in solution.
a) Milk
b) Smoke
c) Fog
d) Sponge
Answer: c) Fog
Explanation: Fog is a colloidal solution in which liquid
droplets are dispersed in air.
a) 0 and 1
b) 1 and 2
c) 0 and infinity
d) -1 and 1
Answer: a) 0 and 1
Explanation: In the Freundlich adsorption isotherm,
is the empirical constant, and its value lies between 0 and 1.
a) Emulsion
b) Sol
c) Aerosol
d) Gel
Answer: a) Emulsion
Explanation: An emulsion is a colloidal system where both the
dispersed phase and the dispersion medium are liquids.
a) Gold sol
b) Starch sol
c) Soap solution
d) Milk
Answer: b) Starch sol
Explanation: Starch sol is stabilized by a protective layer
around particles, not by the charge on particles.
a) Paint
b) Ink
c) Pearls
d) Milk
Answer: c) Pearls
Explanation: A solid sol is a colloidal system in which a solid
is dispersed in another solid.
a) Filtration
b) Centrifugation
c) Dialysis
d) Evaporation
Answer: c) Dialysis
Explanation: Dialysis is used to separate colloidal particles
from the dispersion medium based on the difference in particle size.
a) Adsorption is a spontaneous process
b) Adsorption decreases with an increase in temperature
c) Adsorption is always exothermic
d) All of the above
Answer: d) All of the above
Explanation: Adsorption is a spontaneous, exothermic process,
and it decreases with increasing temperature.
a) Temperature
b) Pressure
c) Volume
d) Concentration of gas
Answer: b) Pressure
Explanation: Adsorption increases with pressure until the
surface is saturated.
a) Aerosols
b) Paints
c) Suspensions
d) Milk of magnesia
Answer: d) Milk of magnesia
Explanation: Milk of magnesia is a colloidal suspension used as
an antacid.
a) Activated charcoal
b) Graphite
c) Silica
d) Iron
Answer: a) Activated charcoal
Explanation: Activated charcoal is commonly used for adsorbing
gases due to its large surface area.
a) Very large
b) Very small
c) Monodispersed
d) Invisible under a microscope
Answer: b) Very small
Explanation: Colloidal particles are typically in the range of
1–100 nm, making them smaller than visible particles.
a) Henry's law
b) Raoult's law
c) Freundlich adsorption isotherm
d) Le Chatelier's principle
Answer: c) Freundlich adsorption isotherm
Explanation: The adsorption of gases on solids is explained by
the Freundlich adsorption isotherm, which is empirical in nature.
a) Emulsion
b) Sol
c) Foam
d) Gel
Answer: a) Emulsion
Explanation: An emulsion is a colloidal system where liquid
droplets are dispersed in another liquid.
a) Sol
b) Gel
c) Emulsion
d) Foam
Answer: a) Sol
Explanation: A sol is a colloidal system in which solid
particles are dispersed in a liquid medium.
a) Dialysis
b) Filtration
c) Centrifugation
d) Distillation
Answer: a) Dialysis
Explanation: Dialysis is a technique to separate colloidal
particles from the dispersion medium using a semipermeable membrane.
a) Emulsion
b) Foam
c) Aerosol
d) Sol
Answer: a) Emulsion
Explanation: An emulsion is a colloidal system formed when one
liquid is dispersed in another liquid.
a) Decreasing the temperature
b) Adding an electrolyte
c) Increasing the dispersion medium
d) Adding a stabilizer
Answer: b) Adding an electrolyte
Explanation: Adding an electrolyte neutralizes the charge on
colloidal particles, leading to coagulation.
a) Smoke
b) Dust
c) Mist
d) Clouds
Answer: b) Dust
Explanation: A solid aerosol is a colloidal system where solid
particles are dispersed in a gas, such as dust in air.
a) Aerosols
b) Emulsions
c) Gels
d) Sols
Answer: b) Emulsions
Explanation: Emulsions can be separated by centrifugation
because the dispersed phase has a greater density than the dispersion medium.
a) Electrostatic repulsion
b) Solvent-solute interaction
c) Presence of charge on particles
d) Protective layer
Answer: d) Protective layer
Explanation: Lyophilic colloids are stabilized due to
solvent-solute interactions and the electrostatic repulsion of particles, not by
protective layers.
a) They are larger than molecules
b) They are visible to the naked eye
c) They cannot pass through a semipermeable membrane
d) They are in a homogeneous phase
Answer: a) They are larger than molecules
Explanation: Colloidal particles are larger than molecules but
smaller than particles in suspensions.
a) Collision with the dispersion medium molecules
b) Absorption of light
c) Electromagnetic forces
d) Internal energy of colloidal particles
Answer: a) Collision with the dispersion medium molecules
Explanation: Brownian motion results from the random collisions
of colloidal particles with the molecules of the dispersion medium.
a) Blood
b) Sponge
c) Gelatin
d) Ink
Answer: c) Gelatin
Explanation: Gelatin forms a gel when mixed with water, making
it an example of a gel.
a) Foam
b) Aerosol
c) Emulsion
d) Sol
Answer: b) Aerosol
Explanation: An aerosol is a colloidal system where solid
particles are dispersed in a gas.
a) Condensation method
b) Dispersion method
c) Coagulation
d) Peptization
Answer: c) Coagulation
Explanation: Coagulation is the process of destabilizing a
colloid, not a method of preparing it.
a) Increases adsorption
b) Decreases adsorption
c) Does not affect adsorption
d) Initially increases, then decreases
Answer: b) Decreases adsorption
Explanation: Adsorption usually decreases with an increase in
temperature.
a) Volume of the adsorbent
b) Surface area of the adsorbent
c) Pressure of the adsorbate
d) Size of the adsorbate molecules
Answer: b) Surface area of the adsorbent
Explanation: The surface area of the adsorbent plays a crucial
role in determining the rate of adsorption.
a) Easily dispersed in water
b) Have a charge on particles
c) Tend to coagulate in water
d) Form stable sols in water
Answer: c) Tend to coagulate in water
Explanation: Hydrophobic colloids tend to coagulate or
aggregate in water due to lack of affinity with the medium.
a) The rate remains constant
b) The rate decreases
c) The rate increases
d) The rate initially increases, then levels off
Answer: d) The rate initially increases, then levels off
Explanation: Initially, adsorption increases with
concentration, but it eventually levels off once the surface is saturated.
a) Mist
b) Smoke
c) Ink
d) Fog
Answer: b) Smoke
Explanation: Smoke is a colloidal system in which solid
particles are dispersed in a gas.
a) Gelatin
b) Rubber in water
c) Milk
d) Butter
Answer: b) Rubber in water
Explanation: Lyophobic colloids do not have an affinity for the
dispersion medium and are not easily formed in water.