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. |