Which of the following catalysts is used in the contact process for the industrial production of sulfuric acid from $SO_2$ and $O_2$ (air)?

Reactions in $Zeolite$ catalysts depend on

Iron $(III)$ catalyses the reaction between iodide and persulphate ions,in which
$A$. $Fe^{3+}$ oxidises the iodide ion
$B$. $Fe^{3+}$ oxidises the persulphate ion
$C$. $Fe^{2+}$ reduces the iodide ion
$D$. $Fe^{2+}$ reduces the persulphate ion
Choose the most appropriate answer from the options given below:

The catalyst and promoter respectively used in the Haber's process of industrial synthesis of ammonia are

The role of a catalyst is to change $ . . . . . . $.

Which of the following statements regarding adsorption theory of heterogeneous catalysis is not correct?