Question

Addition of catalyst in a system
A. Increases equilibrium concentration
B. No effect on equilibrium concentration
C. Decreases equilibrium concentration
D. Increases the rate of forwarding reaction and decreases the rate of backward reaction

Answer 1

Hint: Catalyst has a Greek origin: kata i.e., entirely and lein i.e., to detach.
It makes the rate of the reaction faster and does not get depleted in the process by the process of catalysis.

Complete Step by Step Answer:
The rate of a reaction usually rises after adding the catalyst to a reaction.
It does not get eaten up during the reaction.
It lessens the activation energy of the reactants. It helps in the falling of the energy barrier and thus conversion of reactants into products is much easier.
In a reversible reaction, the catalyst decreases the activation energy of the forward and backward reactions alike.
It does not have any significance on the equilibrium state of a reaction.
Using a catalyst creates no change in the state of the equilibrium because a catalyst increases the speed of the forward and backward reactions equally.
The catalysis does not impact the rates of the two reactions.
As the catalyst does not affect the equilibrium state and hence, does not have any effect on the equilibrium concentration of the reaction as well.
So, B is true.
So, option B is correct.

Note: Catalysts do not impact the rates of the backward or forward reactions. So, it does not affect the equilibrium state and hence, does not retain any effect on the equilibrium concentration of the reaction as well.