1
MCQ (Single Correct Answer)

AIPMT 2014

Which property of colloids is not dependent on the charge on colloidal particles?
A
Coagulation
B
Electrophoresis
C
Electro-osmosis
D
Tyndall effect

Explanation

Tyndall effect is due to the scattering of light by colloidal particles and not due to the charge.
2
MCQ (Single Correct Answer)

AIPMT 2012 Prelims

The protecting power of lyophilic colloidal sol is expressed in terms of
A
coagulation value
B
gold number
C
critical micelle concentration
D
oxidation number

Explanation

The lyophobic sols are less stable than lyophilic sols. The lyophilic sols are thus used to protect the lyophobic sols. This property of lyophilic sols is known as protective action of lyophilic sols.

Which can be represented by gold number. Lesser the gold number, higher is the protecting power.
3
MCQ (Single Correct Answer)

AIPMT 2012 Prelims

Which one of the following statements is incorrect about enzyme catalysis?
A
Enzymes are mostly proteinous in nature.
B
Enzyme action is specific.
C
Enzymes are denatured by ultraviolet rays and at high temperature.
D
enzymes are least reactive at optimum temperature.

Explanation

Enzymes are most reactive at optimum temperature. The optimum temperature for enzyme activity lies between 40°C to 60°C.
4
MCQ (Single Correct Answer)

AIPMT 2012 Prelims

In Freundlich adsorption isotherm, the value of 1/n is
A
between 0 and 1 in all cases
B
between 2 and 4 in all cases
C
1 in case of physical absorption
D
1 in case of chemisorption.

Explanation

Freundlich adsorption isotherm:

$${x \over m} = k.{p^{{1 \over n}}}$$

Where $${x \over m}$$ is the ratio of amount of adsorbent to the amount of adsorbate.

The value of n is always greater than 1. So, the value of $${{1 \over n}}$$ lies between 0 and 1 in all cases.

EXAM MAP

Joint Entrance Examination

JEE Advanced JEE Main

Medical

NEET

Graduate Aptitude Test in Engineering

GATE CSE GATE ECE GATE ME GATE PI GATE EE GATE CE GATE IN