In the case of chemisorption, why adsorption first increases and then decreases with temperature?
Text Solution
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Chemisorption involves activation energy. The initial increase in chemisorption is due to the fact that the heat supplied acts as activation energy and more and more molecules of adsorbate gain energy and possess energy greater than activation energy. Therefore, adsorption increases with increase in temperature. Further increase will increase the energy of the molecules adsorbed and will also increase the rate of desorption. Therefore, the extent of adsorption decreases.
Assertion :- In case of chemical adsorption, (x)/(m) first increase then decrease with temp. Reason :- The intial increase is due to the fact that heat supplied acts as a activation energy. The decrease afterwards is due to the exothermic nature of adsorption at equilibrium.
Which of the following statements is not true? a. Both physisorption and chemisorption are exothermic. b. Physisorption occurs with increase of free energy. c. Physisorption requires low activation energy but chemisorption requires high activation energy. d. The magnitude of chemisorption increases and that of physisorption decreases with rise in temperature.
The correct statements pertaining to the adsorption of a gas on a solid surface are (i) Adsorption is always exothermic (ii) Physisorption may transform into chemisorption at high temperature (iii) Physisorption increases with increasing temperature but chemisorotion decrease with increasing temperature (iv) Chemisorption is more exothermic than physisoption, however, it is very slow due to higher energy of activation
Yhe rate of chemisorption a. increaeses with decreases in temperature b. increases with increasesin tempreture c. increases with decreases in the pressure of gas d. is independent of the pressure of gas
How physical adsorption will be effected by increase in temperature
