Question

The correct statement(s) about surface properties is (are)

• A. The critical temperatures of ethane and nitrogen are 563 K and 126 K, respectively. The adsorption of ethane will be more than that of nitrogen of same amount of activated charcoal at a given temperature.
• B. Cloud is an emulsion type of colloid in which liquid is dispersed phase and gas is dispersion medium.
• C. Adsorption is accompanied by decrease in enthalpy and decrease in entropy of the system.
• D. Brownian motion of colloidal particles does not depend on the size of the particles but depends on viscosity of the solution.

Answer 1

Answer: (A), (C)

The correct options are
A

The critical temperatures of ethane and nitrogen are 563 K and 126 K, respectively. The adsorption of ethane will be more than that of nitrogen of same amount of activated charcoal at a given temperature.

C

Adsorption is accompanied by decrease in enthalpy and decrease in entropy of the system.

Higher the Tc, more easily liquefiable is the gas. This makes it easier to adsorb as well.
$\Delta G<0,\Delta H<0,\Delta S<0$ for adsorption.
Cloud is not an emulsion!
Brownian motion decreases as particle size decreases and viscosity increases.