Question

The catalyst, promoter, and poison for Haber's process are respectively

• A. Platinum, Zinc oxide, Arsenic oxide
• B. Nickel, Chromium trioxide, Carbon monoxide
• C. Platinum, Molybdenum, Hydrogen sulphide
• D. Iron, Molybdenum, Carbon monoxide

Hint:

In Haber's process, iron is the catalyst, molybdenum is a common promoter to enhance the catalyst's efficiency, and carbon monoxide is a poison that deactivates the catalyst.

Answer 1

The Correct Option is D

Haber's process is used for the industrial production of ammonia (\( \text{NH}_3 \)) from nitrogen (\( \text{N}_2 \)) and hydrogen (\( \text{H}_2 \)) under high pressure and moderate temperature. Let's identify the catalyst, promoter, and poison for this process:
- Catalyst: The catalyst in Haber's process is iron (typically in the form of iron oxide, which is reduced to iron during the process). Iron provides a surface for the reaction to occur, increasing the rate of ammonia formation.
- Promoter: Molybdenum is used as a promoter in Haber's process. A promoter enhances the efficiency of the catalyst, often by improving its activity or stability. Molybdenum helps the iron catalyst perform better.
- Poison: Carbon monoxide (\( \text{CO} \)) acts as a poison in Haber's process. A poison deactivates the catalyst by adsorbing onto its surface, blocking active sites, and thus inhibiting the reaction.
Now, let's evaluate the options:
- Option (1): Platinum, Zinc oxide, Arsenic oxide – Incorrect, as platinum is not the catalyst for Haber's process.
- Option (2): Nickel, Chromium trioxide, Carbon monoxide – Incorrect, as nickel is not the catalyst, though carbon monoxide is a poison.
- Option (3): Platinum, Molybdenum, Hydrogen sulphide – Incorrect, as platinum is not the catalyst, though molybdenum is a promoter.
- Option (4): Iron, Molybdenum, Carbon monoxide – Correct, as iron is the catalyst, molybdenum is the promoter, and carbon monoxide is the poison.
So, the correct answer is Iron, Molybdenum, Carbon monoxide.

Answer 2

The catalyst, promoter, and poison for Haber's process are respectively:

Step 1: Understand Haber's process:
Haber's process is an industrial method for synthesizing ammonia (NH₃) from nitrogen (N₂) and hydrogen (H₂) gases. The balanced equation is:
N₂ + 3H₂ ⇌ 2NH₃
This reaction is carried out under high temperature and pressure in the presence of a catalyst.

Step 2: Catalyst used:
The main catalyst used in Haber’s process is iron (Fe). It speeds up the rate of reaction by providing an alternative reaction pathway with a lower activation energy.

Step 3: Promoter used:
A promoter enhances the efficiency of the catalyst. In this case, molybdenum (Mo) is used as a promoter. It improves the durability and activity of the iron catalyst.

Step 4: Poison for the catalyst:
A catalyst poison reduces or destroys the activity of the catalyst. In Haber’s process, carbon monoxide (CO) acts as a poison because it binds strongly to the active sites of the catalyst and inhibits its function.

Conclusion:
- Catalyst: Iron
- Promoter: Molybdenum
- Poison: Carbon monoxide

Final Answer:
\[ \boxed{\text{Iron, Molybdenum, Carbon monoxide}} \]