$A$ catalyst is a substance which

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?

Platinised asbestos helps in the formation of $SO_3$ from $SO_2$ and $O_2$. But,if even a small amount of $As_2O_3$ is present,the platinised asbestos does not help in the formation of $SO_3$. $As_2O_3$ acts here as

In the titration between oxalic acid and acidified potassium permanganate,the manganous salt formed catalyses the reaction. The manganous salt is

Which is True $(T)$ and False $(F)$ of the following statements?
$1.$ By catalyst,the forward reaction becomes fast and the reverse reaction becomes slow.
$2.$ $A$ catalyst decreases the potential energy of reactants and products.
$3.$ $A$ catalyst forms bonds in the reaction,so it is consumed.

Which one of the following statements is not correct?