Question

Consider the reactions
I. \( CO + 3H_2 \xrightarrow{A} CH_4 + H_2O \)
II. \( CO + 2H_2 \xrightarrow{B} CH_3OH \)
III. \( O_2 + 2H_2 \xrightarrow{C} 2H_2O \) The catalysts A, B, C are respectively

• A. Ni, ZnO-\( Cr_2O_3 \), Pt
• B. Pt, ZnO-\( Cr_2O_3 \), Ni
• C. \( CuCl_2 \), Ni, \( V_2O_5 \)
• D. Pd, Pt, ZnO-\( Cr_2O_3 \)

Hint:

Recall the common catalysts used in important industrial processes. Remember that Nickel is often used for hydrogenation reactions, ZnO-\( Cr_2O_3 \) for methanol synthesis from syngas, and noble metals like Platinum for reactions involving hydrogen and oxygen.

Answer 1

The Correct Option is A

Let's identify the catalysts commonly used for each of the given reactions: I.
\( CO + 3H_2 \rightarrow CH_4 + H_2O \) This reaction is the **hydrogenation of carbon monoxide to methane**, also known as the **Sabatier reaction**.
Nickel (Ni) is a common catalyst used for this reaction, often supported on materials like alumina or silica.
II.
\( CO + 2H_2 \rightarrow CH_3OH \) This reaction is the **synthesis of methanol from carbon monoxide and hydrogen**.
A mixture of zinc oxide (ZnO) and chromium(III) oxide (\( Cr_2O_3 \)) is a widely used catalyst for this process, especially at high pressures.
Copper-based catalysts are also used in modern low-pressure methanol synthesis.
However, among the given options, ZnO-\( Cr_2O_3 \) is the most fitting catalyst for this reaction under typical conditions implied.
III.
\( O_2 + 2H_2 \rightarrow 2H_2O \) This is the **reaction of hydrogen and oxygen to form water**.
Platinum (Pt) is a highly effective catalyst for this exothermic reaction, even at room temperature.
Other noble metals like palladium (Pd) can also catalyze this reaction.
Based on these common catalysts for each reaction: - Catalyst A (for reaction I) is Nickel (Ni).
- Catalyst B (for reaction II) is Zinc oxide-Chromium(III) oxide (ZnO-\( Cr_2O_3 \)).
- Catalyst C (for reaction III) is Platinum (Pt).
Therefore, the catalysts A, B, and C are Ni, ZnO-\( Cr_2O_3 \), and Pt, respectively.
This corresponds to option (A).