Free Solutions and Colloids MCQs with Answers

• A. Temperature fluctuation within the liquid phase.
• B. Attraction and repulsion between charges on the colloidal particles.
• C. Impact of the molecules of the dispersion medium on the colloidal particles.
• D. Convectional currents.

Explanation: Brownian motion is the random movement of the low weight particles suspended in a fluid.

• A. electrostatic potential
• B. sedimentation potential
• C. zeta potential
• D. chemical potential

Explanation: The potential differences existing between the surfaces of a solid particle immersed in a conducting liquid (e.g.

• A. the amount of gold present in the colloid.
• B. the amount of gold required to break the colloid.
• C. the amount of gold required to protect the colloid.
• D. none of the above.

Explanation: Gold number is 'least quantity of protective colloid in milligrams, which is just sufficient to prevent the coagulation of 10 ml of…

• A. Peptization
• B. Dialysis
• C. Protection
• D. Dissolution

Explanation: Peptization is the process responsible for the formation of stable dispersion of colloidal particles in dispersion medium.

• A. Positive charge
• B. Negative charge
• C. Sometimes positive and sometimes negative charge
• D. No charge

Explanation: The sol particle will carry positive charge.

• A. The viscosity of the medium
• B. The surface tension of the medium
• C. Both (A) and (B)
• D. The formation of an eletrical layer between the two phases

Explanation: Due to preferential adsorption of similar ions, an electrical double layer formed on the surface of colloidal particles. e.g.

• A. to improve the flavour
• B. to cause the mixture to solidify
• C. to stabilize the colloid and prevent crystal growth
• D. to prevent the formation of a colloid

Explanation: This is due to stabilize the colloid and prevent crystal growth.

• A. 0.025
• B. 0.25
• C. 2.5
• D. 250

Explanation: Gold number is 'least quantity of protective colloid in milligrams, which is just sufficient to prevent the coagulation of 10 ml of…

• A. It increases the equilibrium concentration of the products
• B. It is a substance which change the equilibrium constant of the reacting ion.
• C. It shortens the time to reach equilibrium.
• D. It supplies energy to the reaction.

Explanation: A catalyst is substance that increases rate of reaction and it shortens the to reach equilibrium.

• A. A solution of AgNO3 in HNO3
• B. Colloidal solution of gold
• C. A colloidal solution of platinum
• D. A colloidal solution of palladium

Explanation: Purple of Cassius is colloidal solution of gold. It is formed by the reaction of gold salts with tin(II) chloride.

• A. Some times physical adsorption pass over to chemisorption on increasing the temperature of the system.
• B. Oxygen is adsorbed on charcoal but on desorption it also releases CO and CO2
• C. Only lighter gases show physical adsorption at low temp.
• D. Activation energy of chemisorption > activation energy of physical adsorption

Explanation: All gases show the physical adsorption at low temperature.

• A. presence of different types of foreign particles depending upon the method of preparation of the colloid
• B. different concentrations of gold
• C. various forms of gold
• D. presence of different size of the colloidal particles obtained in different methods.

Explanation: Colloidal solutions of gold prepared by different methods have different colors due to the presence of different size of the colloidal…

• A. the clouds are attracted towards the electrical charge on the earth.
• B. large amount of water is present in the cloud
• C. dense clouds are present in the upper atmosphere
• D. mutual discharge of oppositely charged clouds resulting in the coagulation of water droplets

Explanation: This is due to mutual discharge oppositely charge clouds resulting in the coagulation of water droplets.

• A. Coagulation of sand
• B. sedimentation of common salt
• C. deposition of MgCl2
• D. mutual coagulation

Explanation: Sand is a negatively charged colloidal particles, which is carried by river to the ocean which is a vast reservoir of Na+, Mg+,K+, ion.

• A. It seals the blood cell
• B. Blood starts flowing in reverse direction
• C. The blood is coagulated and the blood cell is sealed
• D. None

Explanation: Blood is a colloidal solution of albuminoid substance in water and alubminoid is negatively charged.

• A. disperson effect
• B. scattering
• C. reflection
• D. transmission

Explanation: The sky or water in the sea looks blue because the light of long wavelength gets absorbed, and light of short wavelength (blue light) gets…

• A. Silica gel
• B. Alumina
• C. Fuller's earth
• D. Activated charcol

Explanation: The adsorbents commonly employed for chromatography are alumina (specially prepared for this purpose), magnesium oxide, and sucrose.

• A. Cl− ions
• B. Fe3+ ions
• C. OH− ions
• D. Fe+2 ions

Explanation: Fe(OH)3 is a positive sol. The positive charge is due to the preferential adsorption of Fe3+ ions.

• A. Colloids
• B. Crystalloids
• C. Electrolytes
• D. Non electrolytes

Explanation: Solutions which can diffuse readily through parchment membrane are crystalloids.

• A. Is easy to spray at high altitude
• B. Is easy to synthesizes
• C. Has crystal structure similar to ice
• D. Is insoluble in water

Explanation: AgI has the crystal structure similar to ice. Hence it can act as a nucleus for the precipitation of the water molecules and causes rain.