Which of the following is not required in the Solvay's process for the manufacture of `Na_2CO_3`?

Options

A. `NH_3`
B. `CO_2`
C. NaCl
D. CO

Answer

To solve the question regarding which substance is not required in the Solvay process for the manufacture of sodium carbonate (Na₂CO₃), we can follow these steps:

### Step 1: Understand the Solvay Process
The Solvay process is a method for producing sodium carbonate from sodium chloride (NaCl), ammonia (NH₃), and carbon dioxide (CO₂). It involves several steps where these reactants interact to form sodium carbonate.

### Step 2: Identify the Required Components
From the Solvay process, we know that the following components are essential:
- **Ammonia (NH₃)**: Used in the process to react with carbon dioxide and sodium chloride.
- **Carbon Dioxide (CO₂)**: Reacts with ammonia and sodium chloride to form sodium bicarbonate (NaHCO₃).
- **Sodium Chloride (NaCl)**: The source of sodium ions for the production of sodium carbonate.

### Step 3: Analyze the Given Options
Now, let's analyze the options provided in the question:
1. Ammonia (NH₃) - Required
2. Carbon Dioxide (CO₂) - Required
3. Sodium Chloride (NaCl) - Required
4. Carbon Monoxide (CO) - Not required

### Step 4: Conclusion
Since carbon monoxide (CO) is not used in the Solvay process, the correct answer to the question is that carbon monoxide is not required for the manufacture of sodium carbonate.

### Final Answer
The substance that is not required in the Solvay process for the manufacture of Na₂CO₃ is **Carbon Monoxide (CO)**.

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