Incorrect statement regarding adsorption is:
1. | Adsorption is a surface phenomenon of accumulation of molecules of a substance at the surface rather than in the bulk of a solid or liquid. |
2. | Adsorption involves penetration through the surface to the bulk of the solid or liquid. |
3. | The substance that gets adsorbed is called the ‘adsorbate’ and the substance on whose surface the adsorption takes place is called the ‘adsorbent’. |
4. | During absorption, the substance gets uniformly distributed throughout the bulk of the solid or liquid. |
Why is a finely divided substance more effective as an adsorbent?
1. Small surface area.
2. Large surface area.
3. Weak molecular bonding.
4. Strong molecular bonding.
The factors that influence the adsorption of a gas on a solid is/are:
1. Nature of the gas.
2. Surface area of the solid.
3. Effect of pressure.
4. All of the above.
An adsorption isotherm is a plot between:
1. | The extent of adsorption \(({x \over m})\) against the pressure of gas (P) at constant V. |
2. | The extent of adsorption \(({x \over m})\) against the pressure of gas (P) at constant T. |
3. | The extent of absorption \(({x \over m})\) against the volume of gas (V) at constant P. |
4. | The extent of absorption \(({x \over m})\) against the pressure of gas (P) at constant T. |
Adsorbent can be activated by:
1. | Increasing the surface area of the adsorbent. |
2. | Breaking adsorbent into smaller pieces or powdering it. |
3. | Both (1) and (2) |
4. | None of the above. |
The probable reasons of the exothermic nature of adsorption is:
1. | Adsorption leads to a decrease in the residual forces on the surface of the adsorbent. |
2. | ∆S is negative. |
3. | Both (1) and (2) |
4. | None of the above. |
Which of the following statement is false?
1. | Adsorption is a reversible process and is accompanied by a decrease in pressure. |
2. | Adsorption decreases with an increase in pressure. |
3. | Adsorption is an exothermic process. |
4. | The magnitude of physisorption adsorption decreases with an increase in temperature. |
Which of the following statement about multi-molecular colloid is incorrect?
1. | They have a diameter of less than 1 nm. |
2. | When these particles are dissolved in a liquid, they form sol. |
3. | The molecules in the aggregate are held together by van der Waal’s forces of attraction. |
4. | None of the above. |
Enzymes are:
1. Biochemical catalysts.
2. Protein molecules of high molecular masses.
3. Both (1) and (2)
4. None of the above.
The phenomenon of the scattering of light by a colloidal solution known as:
1. Zeeman effect.
2. Tyndall effect.
3. Electrophoresis.
4. None of the above.