Which raw material is used in the preparation of soft glass ?

Options

A. `K_(2)CO_(3),SiO_(2),CaCO_(3)`
B. `K_(2)CO_(3),SiO_(2),PbCO_(3)`
C. `Na_(2)CO_(3),SiO_2,CaCO_(3)`
D. `Na_(2)CO_(3),SiO_(2),PbO`

Explanation

To determine the raw material used in the preparation of soft glass, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Glass Composition**:
- Glass is primarily made up of three main components: silica (SiO2), lime (CaO), and alkali metal carbonates.

2. **Identifying Soft Glass**:
- Soft glass is a specific type of glass that has a lower melting point compared to other types of glass. It is typically composed of silica, lime, and sodium carbonate.

3. **Components of Soft Glass**:
- **Silica**: The primary component, which is silicon dioxide (SiO2).
- **Lime**: This is usually derived from limestone, which is calcium carbonate (CaCO3).
- **Alkali Metal Carbonate**: The common alkali metal carbonate used in soft glass is sodium carbonate (Na2CO3).

4. **Conclusion**:
- The raw materials used in the preparation of soft glass are silica (SiO2), lime (CaCO3), and sodium carbonate (Na2CO3).

5. **Final Answer**:
- Therefore, the correct raw materials for the preparation of soft glass are **SiO2, CaCO3, and Na2CO3**.