Sodium Carbonate is prepared on large scale by

Options

A. Solvay's process
B. Beckmann's plants
C. Hesenclover plant
D. adding water to lime

Answer

**Step-by-Step Solution:**

1. **Understanding Sodium Carbonate**: Sodium carbonate, commonly known as soda ash, has the chemical formula Na2CO3. It is an important industrial chemical used in glass manufacturing, detergents, and various chemical processes.

2. **Identifying the Preparation Method**: The question asks for the method used for the large-scale preparation of sodium carbonate. The most widely used method for this purpose is the **Solvay process**.

3. **Overview of the Solvay Process**:
- The Solvay process involves several key steps to produce sodium carbonate from sodium chloride (common salt) and limestone (calcium carbonate).

4. **Step 1 - Reaction of Carbon Dioxide and Ammonia**:
- In the first step, carbon dioxide (CO2) is reacted with dissolved ammonia (NH3) in water. This forms ammonium bicarbonate (NH4HCO3).

5. **Step 2 - Formation of Sodium Bicarbonate**:
- Ammonium bicarbonate is then reacted with sodium chloride (NaCl) to produce sodium bicarbonate (NaHCO3) and ammonium chloride (NH4Cl).

6. **Step 3 - Crystallization of Sodium Bicarbonate**:
- The sodium bicarbonate formed is less soluble in water, so it crystallizes out of the solution. The crystals are then separated from the solution.

7. **Step 4 - Heating to Form Sodium Carbonate**:
- The sodium bicarbonate crystals are heated (calcined) to produce sodium carbonate, carbon dioxide, and water. The reaction is as follows:
\[ 2 \text{NaHCO}_3 \rightarrow \text{Na}_2\text{CO}_3 + \text{CO}_2 + \text{H}_2\text{O} \]

8. **Conclusion**:
- Therefore, the large-scale preparation of sodium carbonate is achieved through the **Solvay process**.

**Final Answer**: Sodium carbonate is prepared on a large scale by the Solvay process.

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