Home
Class 12
CHEMISTRY
Why physisorption is multi-molecular whe...

Why physisorption is multi-molecular whereas chemisorption is unimolecular ?

Text Solution

Verified by Experts

There are weak van der Waals force of attraction between adsorbent and adsorbate in physisorption. It is non-specifie and reversible. Chemisorption involves strong forces of chemical nature. It highly specific and irreversible in nature.
Promotional Banner

Topper's Solved these Questions

  • SURFACE CHEMISTRY

    CENGAGE CHEMISTRY ENGLISH|Exercise Ex 5.1|11 Videos

  • SURFACE CHEMISTRY

    CENGAGE CHEMISTRY ENGLISH|Exercise Ex 5.2|11 Videos

  • SURFACE CHEMISTRY

    CENGAGE CHEMISTRY ENGLISH|Exercise Illustration 5.36|1 Videos

  • SOLUTIONS

    CENGAGE CHEMISTRY ENGLISH|Exercise Ex 2.3 (Objective)|9 Videos

  • SYNTHETIC AND NATURAL POLYMERS

    CENGAGE CHEMISTRY ENGLISH|Exercise Exercises Assertion Reasoning|10 Videos

Similar Questions

Explore conceptually related problems

Why heat of chemisorption is more than heat of physisorption?

Which forms multi molecular layers during adsorption :

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.

Given an example where physisorption changes to chemisorption with rise in temperature. Explain the reason for change.

Chemisorption forms ………………. Molecular layers .

Adsorption is the tendency of accumulation of molecular species at the surface of solid or liquid. Depending upon the nature of bonds or forces of attraction between adsorbate and adsorbent. It is classofied between physisorption and chemisorption. Which of the following gas molecules have maximum value enthalpy of physisorption?

The correct statement(s) pertaining to the adsorption of a gas on a solid surface is(are) (i) adsorption is always exothermic (ii) physisorption may transform into chemsisorption transform into chemisorption at high temperature (iii) physisorption increases with increasing temperature but chemisorption decreases with increasing temperature . (iv) chemisorption is more exothermic than physisorption , however it is very slow due to higher energy of activation.

Why does physisorption decrease with increase of temperature ?

Distinguish between physisorption and chemisorption.

Of physisorption and chemisorption which type of adsorption has a higher enthalphy of adsorption ?

CENGAGE CHEMISTRY ENGLISH-SURFACE CHEMISTRY-Solved Examples
  1. What is the difference between multi-molecular and macromolecular coll...

    Text Solution

    |

  2. Physical and chemical adsorption respond differenlty with a rise in te...

    Text Solution

    |

  3. A small amount of silica gel and anhydrous calcium chloride are placed...

    Text Solution

    |

  4. How is adsorption of a gas related to its critical temperature?

    Text Solution

    |

  5. Explain the following observation: a. Lyphilic colloid is more stabl...

    Text Solution

    |

  6. Give one test to distinguish whether the given emulsion is oil-in-wate...

    Text Solution

    |

  7. Consider the adsorption isotherm given below and interpret the variati...

    Text Solution

    |

  8. A colloidal solution of Agl is prepared by two different methods as sh...

    Text Solution

    |

  9. Adsorption and Absorption are same. True/False?

    Text Solution

    |

  10. Adsorption, if spontaneous, is exothermic. Explain.

    Text Solution

    |

  11. In a coagulation experiment, 5mL of As(2)S(3) is mixed with distilled...

    Text Solution

    |

  12. In an adsorption experiment, a graph between log (x/m) versus log P wa...

    Text Solution

    |

  13. The volume of nitrogen gas Vm (at STP) reqired to cover a sample of si...

    Text Solution

    |

  14. 100mL of a colloidal solution is completely precipitated by addition o...

    Text Solution

    |

  15. What is the charge on the colloidal particles in the following ? a. ...

    Text Solution

    |

  16. which of the following is most effective in coagulating ferric hydroxi...

    Text Solution

    |

  17. Write a mathematical expression showing relationship between the amoun...

    Text Solution

    |

  18. In the case of chemisorption, why adsorption first increases and then ...

    Text Solution

    |

  19. Why physisorption is multi-molecular whereas chemisorption is unimolec...

    Text Solution

    |

  20. What happens when freshly precipitated Fe(OH)3 is shaken with small am...

    Text Solution

    |