H₂ gas is adsorbed on activated charcoal to a very little extent in comparion to easily liquefiable gases due to................................ .

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(a)

very strong van der Waals interaction

(b)

very weak van der Waals forces

(c)

very low critical temperature

(d)

very high critaical temperature

An emulsion cannot be broken by.........................and......................... .

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(a)

heating

(b)

adding more amount of dispersion medium

(c)

freezing

(d)

adding emulsisying agent

Which of the following colloids cannot be coagulated easily?

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(a)

Lyophobic colloids

(b)

Irreversible colloids

(c)

Reversible colloids

(d)

Lyophilic colloids

Which phenomenon occurs when an electric field is applied to a colloidal solution and electrophoresis is prevented?

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(a)

Reverse osmosis takes place

(b)

Electroosmosis takes place

(c)

Dispersion medium begins to move

(d)

Dispersion medium becomes stationary

Which of the following phenomenon occurs when a chalk stick is dipped in ink?

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(a)

adsorption of coloured sustance

(b)

adsorption of solvent

(c)

adsorption and dsorption both of solvent

(d)

absorption of solvent