In the manufacture of $H_2SO_4$ by the contact process,$As_2O_3$ acts as a .......

Which one of the following statements is incorrect in the case of heterogeneous catalysis?

Adsorption theory is applicable for

Which reaction characteristics are changing by the addition of a catalyst to a reaction at constant temperature: $(i)$ Activation energy,$(ii)$ Equilibrium constant,$(iii)$ Reaction entropy,$(iv)$ Reaction enthalpy?

In which of the following processes is platinum used as a catalyst?

Platinized asbestos is used as a catalyst in the manufacture of $H_2SO_4$. It is an example of