Sodium carbonate is prepared by Solvay process. Which of the following compounds is obtained as a by - product?

Options

A. `NH_(4)Cl`
B. `NH_(3)`
C. `CO_(2)`
D. `CaCl_(2)`

Answer

To solve the question regarding the by-product obtained in the Solvay process for the preparation of sodium carbonate, we can follow these steps:

### Step 1: Understand the Solvay Process
The Solvay process is an industrial method used to produce sodium carbonate (Na2CO3) from sodium chloride (NaCl) and calcium carbonate (CaCO3).

### Step 2: Identify the Reactants
The main reactants in the Solvay process are:
- Sodium chloride (NaCl), which is found in brine solution.
- Calcium carbonate (CaCO3), commonly known as limestone.

### Step 3: Write the Chemical Reaction
The overall reaction for the Solvay process can be written as:
\[ 2 \text{NaCl} + \text{CaCO}_3 \rightarrow \text{Na}_2\text{CO}_3 + \text{CaCl}_2 \]

### Step 4: Identify the Products
From the balanced equation, we can see that the products formed are:
- Sodium carbonate (Na2CO3)
- Calcium chloride (CaCl2)

### Step 5: Determine the By-Product
In this reaction, the compound that is obtained as a by-product is calcium chloride (CaCl2).

### Conclusion
Thus, the by-product obtained in the Solvay process for the preparation of sodium carbonate is calcium chloride (CaCl2).

### Final Answer
The correct option is calcium chloride (CaCl2).

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