SURFACE CHEMISTRY Set 5

Intermediate compound formation theory ✘ Adsorption theory ✘ A combination of two theories, intermediate compound formation and adsorption theory ✘ None of the above ✔ NULL ✔ NULL NULL

Metals with variable valency ✘ Metals with non-variable valency ✘ Non-metals with fixed valency ✘ Inert gases ✔ NULL ✔ NULL NULL

Is easy to spray at high altitudes ✘ Is easy to synthesize ✘ Has crystal structure similar to ice ✘ Is insoluble in water ✔ NULL ✔ NULL NULL

The shape of the catalyst ✘ The specificity of the catalyst ✘ The size of the pores of catalyst which can trap selective molecules only ✘ Their use for only some selected reaction ✔ NULL ✔ NULL NULL

None-specific nature ✘ High specificity ✘ Irreversibility ✘ All of these ✔ NULL ✔ NULL NULL

Colloidal state ✘ Solid state ✘ Solution state ✘ None of these ✔ NULL ✔ NULL NULL

Iron ✘ Finally divided nickel ✘ ✘ Anhydrous ✔ NULL ✔ NULL NULL

Caffeine ✘ Calciferol ✘ Keratin ✘ Casein ✔ NULL ✔ NULL NULL

Physical adsorption is due to van der Waals' forces ✘ Physical adsorption decreases at high temperature and low pressure ✘ Physical adsorption is reversible ✘ Adsorption energy for a chemical adsorption is generally lesser than that of physical adsorption ✔ NULL ✔ NULL NULL

✘ ✘ ✘ ✔ NULL ✔ NULL NULL