Give two important characteristics of physisorption.

In case of chemisorption, why adsorption first increases and then decreases with temperature?

Which will be adsorbed more readily on the surface of charcoal and why? NH₃ or CO₂?

Heat of adsorption is greater for chemisorptions than physisorption. Why?

Peptising agent is added to convert precipitate into colloidal solution. Explain with an example.

What happens when a colloidal sol of Fe(OH)₃ and As₂S₃ are mixed?

Why are lyophillic colloidal sols are more stable than lyophobic colloidal sol.

Addition of Alum purifies water. Why?

What are enzymes? Write a brief note on the mechanism of enzyme catalysis.

What do you mean by activity and selectivity of catalyst?

Describe some feature of catalysis by Zeolites.

Why does bleeding stop by rubbing moist alum

Why is desorption important for a substance to act as good catalyst?

Comment on the statement: Colloid is not a substance but it is a state of substance.

Explain any one method for coagulation.

The mechanism of Fridel crafts reaction is given below
\({ C }_{ 6 }{ H }_{ 5 }+{ { CH }_{ 3 }Cl\overset { anhydrous\\ \quad { Alcl }_{ 3 } }{ \longrightarrow } }{ C }_{ 6 }{ H }_{ 5 }{ CH }_{ 3 }+HCl\)

Thermal decomposition of KClO₃  in presence of MnO₂ proceeds as follows.
Steps in the reaction 2KClO₃  → 2KCl + 3O₂ can be given as

Formation of water due to the reaction of H₂ and O₂ in the presence of Cu proceeds as follows. Steps in the reaction H₂ + 1/2O₂ → H₂O can be given as

Oxidation of HCl by air in presence of CuCl₂ proceeds as follows