Question

Which of the following statements regarding catalysts are true?
A. A catalyst remains unchanged in composition and quantity at the end of the reaction.
B. A catalyst can initiate a reaction.
C. A catalyst can alter the reaction rate in both directions.
D. Catalysts are sometimes very specific in respect of the reaction.

Answer 1

Hint: Catalysts are the substances which increase the rate of a reaction under different conditions. Catalysts are not consumed in a reaction.

Complete Step by Step Solution:
A. When a catalyst is added in a reaction, it does not take part in the reaction but affects the reaction and the quantity of product at the end of the reaction. Therefore, the statement is true.
B. The catalyst increases the rate of reaction but does not initiate a reaction. Therefore, the statement is false.
C. A catalyst pushes the reaction in both the forward and backward reaction in a reversible reaction. Therefore, the statement is true.
D. Catalysts are specific for different types of reactions. Different reactions use different catalysts. Therefore, the statement is true.
Therefore, options A, C and D are correct.
Additional information: The process by which the reaction rate is increased by adding a catalyst is known as catalysis. A few examples of catalysts are palladium, platinum, iron, nickel, and zeolites.

Note: Catalyst and enzyme have the same effect on the reaction but they are different from each other. Enzymes are naturally occurring whereas catalysts can be synthesised. All enzymes act as a catalyst but all catalyst is not an enzyme.