Animal charcoal is used in decolorising colour of liquids because it is a good

• adsorbate

• adsorbent

• oxidising agent

• reducing agent

Which one of the following statements is not correct?

• Physical adsorption decreases with increase in the temperature

• Physical adsorption is multtlayered

• Activation energy of physical adsorption is very high

• Enthalpy change of physical adsorption is about 20 kJ mol

Which one of the following equations represents Freundlich adsorption isotherm ?

• $\frac{\mathrm{x}}{\mathrm{m}}= \mathrm{Kp}$

• $\frac{\mathrm{x}}{\mathrm{m}}= {\mathrm{Kp}}^{\mathrm{n}}$

• $\log \frac{\mathrm{x}}{\mathrm{m}}= {\mathrm{Kp}}^{\mathrm{n}}$

• $\log \frac{\mathrm{x}}{\mathrm{m}}= \mathrm{Kn} \log \mathrm{p}$

Which of the following is a lyophobic colloidal solution?

• Aqueous starch solution

• Aqueous protein solution

• Gold sol

• Polymer solutons in some organic solvents

Which of the following is an example for heterogeneous catalysis reaction ?

• $2{\mathrm{SO}}_2\left(\mathrm{g}\right) + {\mathrm{O}}_2\left(\mathrm{g}\right) \stackrel{\mathrm{NO}\left(\mathrm{g}\right) }{\to }2{\mathrm{SO}}_3 \left(\mathrm{g}\right)$

• Hydrolysis of aqueous sucrose solution in the presence of aqueous mineral acid

• $2{\mathrm{H}}_2{\mathrm{O}}_2 \left(\mathrm{l}\right) \stackrel{\mathrm{Pt}\left(\mathrm{s}\right) }{\to }2{\mathrm{H}}_2\mathrm{O} \left(\mathrm{l}\right) + {\mathrm{O}}_2 \left(\mathrm{g}\right)$

• Hydrolysis of liquid in the presence of aqueous mineral acid

The disperse phase, dispersion medium and nature of colloidal solution (lyophilic or lyophobic) of 'gold sol' respectively are :

• solid, solid, lyophobic

• liquid, liquid, lyophobic

• solid, liquid, lyophobic

• solid, liquid, lyophilic

307.

Assertion (A) : A catalyst increases the rate of a reaction.

Reason (R) : In presence of a catalyst, the activation energy of the reaction increases.

The correct answer is

• Both (A) and (R) are true and (R) is the correct explanation of (A).

• Both (A) and (R) are true but (R) is not the correct explanation of (A).

• (A) is true, but (R) is not true

• (A) is not true, but (R) is true

Which one of the following graphs represents Freundlich adsorption isotherm ?

Which of the following is not correct?

• Milk is a naturally occurring emulsion

• Gold sol is a lyophilic sol

• Physical adsorption decreases with rise in temperature

• Chemical adsorption is unilayered

Which one of the following gives a straight line for Freundlich adsorption isotherm?

• log $\frac{\mathrm{x}}{\mathrm{m}}$ vs log p

• $\frac{\mathrm{x}}{\mathrm{m}} \mathrm{vs} \frac{1}{\mathrm{p}}$

• log $\frac{\mathrm{x}}{\mathrm{m}} \mathrm{vs} \log \frac{1}{\mathrm{p}}$

• $\frac{\mathrm{x}}{\mathrm{m}} \mathrm{vsp}$