Sodium carbonate is prepared by …….and its formula is ……. .

Explanation

To answer the question about the preparation of sodium carbonate and its formula, we can break it down into clear steps:

### Step-by-Step Solution:

1. **Identify the Reactants**: Sodium carbonate (Na2CO3) is prepared from sodium chloride (NaCl), carbon dioxide (CO2), ammonia (NH3), and water (H2O).

2. **Initial Reaction**: The first step involves the reaction of sodium chloride, carbon dioxide, ammonia, and water to form sodium bicarbonate (NaHCO3) and ammonium chloride (NH4Cl). The reaction can be represented as:
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