Sodium carbonate can be manufactured by Solvay's process but potassium carbonate cannot be prepared because :

Options

A. `K_(2)CO_(3)` is more soluble
B. `K_(2)CO_(3)` is less soluble
C. `KHCO_(3)` is more soluble than `NaHCO_(3)`
D. `KHCO_(3)` is less soluble than `NaHCO_(3)`.

Answer

To solve the question regarding why potassium carbonate (K2CO3) cannot be prepared by the Solvay process while sodium carbonate (Na2CO3) can, we will analyze the process step by step.

### Step-by-Step Solution:

1. **Understanding the Solvay Process**:
- The Solvay process is a method for producing sodium carbonate from sodium chloride (NaCl), ammonia (NH3), and carbon dioxide (CO2).
- The process involves the formation of sodium bicarbonate (NaHCO3) as a precipitate, which is then heated to produce sodium carbonate.

2. **Formation of Sodium Bicarbonate**:
- In the Solvay process, when NH3 and CO2 are bubbled through a solution of NaCl, sodium bicarbonate (NaHCO3) precipitates out because it is not very soluble in water.

3. **Heating to Produce Sodium Carbonate**:
- The precipitated NaHCO3 is filtered, dried, and then heated to produce Na2CO3, CO2, and water. This step is crucial because the precipitation of NaHCO3 allows for the subsequent production of Na2CO3.

4. **Attempting to Use Potassium Chloride**:
- If we attempt to use potassium chloride (KCl) instead of NaCl in the Solvay process, we would expect a similar reaction. However, the product formed would be potassium bicarbonate (KHCO3).

5. **Solubility of Potassium Bicarbonate**:
- The key issue arises with KHCO3. Unlike NaHCO3, potassium bicarbonate is more soluble in water. This means that it does not precipitate out of the solution.

6. **Conclusion**:
- Since KHCO3 does not precipitate, we cannot isolate it as a solid to further heat and convert it into K2CO3. This is the reason why potassium carbonate cannot be manufactured using the Solvay process.

7. **Identifying the Correct Option**:
- Among the given options:
- Option A: K2CO3 is more soluble (not relevant).
- Option B: K2CO3 is less soluble (not relevant).
- Option C: KHCO3 is more soluble than NaHCO3 (this is true and explains why K2CO3 cannot be prepared).
- Option D: KHCO3 is less soluble than NaHCO3 (this is false).
- Therefore, the correct answer is **Option C**: KHCO3 is more soluble than NaHCO3.