Effect of Catalyst

Q.

The energies of activation for forward and reverse reactions for $A_2+B_2\rightleftharpoons 2AB$ are $180kJmo{l}^{-1}$ and $200kJmo{l}^{-1}$ respectively. The presence of a catalyst lowers activation energy of both reactions by $100kJmo{l}^{-1}$. The enthalpy change of the reaction $(A_2+B_2\to 2AB)$ in the presence of a catalyst will be (in kJ $mo{l}^{-1}$)

1. 20

2. 300

3. 120

4. 280

Q.

A catalyst is a substance that alters the rate of a chemical reaction.

1. True
2. False

Q. Which of the following statements regarding catalyst is not true?

1. A catalyst remains unchanged in composition and quantity at the end of the reaction.
2. A catalyst can alter the Gibbs free energy change.
3. A catalyst does not alter the equilibrium in a reversible reaction.
4. Catalysts are sometimes very specific in respect of reaction.

Q.

The first step in the manufacture of nitric acid is the catalytic oxidation of ammonia. What is name of the catalyst?

1. Finely divided iro

2. Platinum

3. Vanadium pentoxide

4. Molybdenum