Define a catalyst.

Give an example of a catalyst.

State an important characteristic of enzyme as catalyst.

How is activation energy affected by the use of a catalyst.

Explain bromination of benzene requires FeBr_3 as catalyst, while bromination of anisole (C_6H_5OCH_3) does not require any catalyst.

The activation energy of a reaction is 80"kj.mol"^(-1) . The activation energy reduces by 75% in presence of a catalyst. If the other parameters are kept constant , compare the rates of the reaction in presence and absence of the catalyst at 25^(@)C .

Which one is the correct factor that explains the increase of rate of reaction by a catalyst

At a given temperature , for a reaction , the activation energy in absence of catalyst is greater than that in presence of catalyst be an amount of RT. If the value of the rate constant in presence of catalyst is x times that in absence of catalyst, then find the value of x.

The role of a catalyst is to change -

Give an example of negative catalyst.