Question

1. Why metals or their compounds (like metal oxides, metal hydroxides, metal complexes, etc.) that are strong chemical reactants are not generally good catalysts?  

2. Briefly describe why study of mechanisms of the absorption and desorption processes helps us understand catalysis.

Answer 1

(M²⁺ to M³⁺ )

1) Their redox couple should have huge electron volt difference

    For the good catalytic process ,   

   these two oxidation states should be easily interconvertible

Most of metal ions does not have this properties

Metal tends to under go easy oxidation

2. Adsorption is classified into two types    i) chemisorption ( covalent bond is formed between the adsorbate and adsorbed molecules)

                                                            II) Physisorption    ( electrostatic interaction or deposition or filling property)

Chemisorption may alter bond energy of the moelcule adsorbed on the surface of the solid, Then bond will be easilby breakable

(breaking a bond will to lead formation new bond    this will produce new compounds,

Once the product is formed, that should desorbed from the surface of the solid.

adsorption and desorption mechanism is important in the heterogeneous Fenton reaction