Question

In the Haber process of ammonia preparation, the catalyst and the promoter are

• A. Reduced Fe$_2$O$_3$ and Al$_2$O$_3$ respectively
• B. Reduced Fe$_2$O$_3$ and Mn$_2$O$_3$ respectively
• C. Reduced Al$_2$O$_3$ and Fe$_2$O$_3$ respectively
• D. Reduced Mn$_2$O$_3$ and Al$_2$O$_3$ respectively

Hint:

In the Haber process, remember: iron is the catalyst (often from Fe$_2$O$_3$), and Al$_2$O$_3$ is the promoter. Promoters enhance catalyst performance without directly participating in the reaction.

Answer 1

The Correct Option is A

The Haber process is a critical industrial method for the synthesis of ammonia (NH$_3$) from nitrogen (N$_2$) and hydrogen (H$_2$) gases.
The reaction is represented as:
\[ \text{N}_2 + 3\text{H}_2 \rightleftharpoons 2\text{NH}_3 + \Delta H \]
This reaction is exothermic and requires a catalyst to increase the rate of reaction and improve yield under optimal temperature and pressure.
Catalyst: The active catalyst used in the Haber process is finely divided iron (Fe), typically derived from reduced iron oxide (Fe$_2$O$_3$).
Promoter: Promoters are substances that enhance the efficiency and longevity of the catalyst. In this case, Aluminum oxide (Al$_2$O$_3$) acts as the promoter. It helps prevent the sintering (clumping) of iron particles and increases the surface area.
Other common promoters may include K$_2$O and CaO, but in this question, among the options listed, Al$_2$O$_3$ is the correct match.
Incorrect options involve reverse roles or less common/non-promoter materials such as Mn$_2$O$_3$, which is not typically used in the Haber process.
Thus, the correct catalyst and promoter pair is:
Reduced Fe$_2$O$_3$ and Al$_2$O$_3$ respectively.