Soda ash is

Options

A. `Na_(2)CO_(3).H_(2)O`
B. NaOH
C. `Na_(2)CO_(3)`
D. `NaHCO_(3)`

Answer

To answer the question "Soda ash is," we need to identify what soda ash is and its chemical formula.

### Step-by-Step Solution:

1. **Definition of Soda Ash**: Soda ash is a common name for sodium carbonate, which is an inorganic compound.

2. **Chemical Formula**: The chemical formula for soda ash is Na₂CO₃. This indicates that it consists of two sodium (Na) ions, one carbon (C) atom, and three oxygen (O) atoms.

3. **Common Names**: Soda ash is also known as "calcined soda" when it is in its anhydrous form (without water).

4. **Hydrated Forms**: There are hydrated forms of sodium carbonate, such as washing soda, which is sodium carbonate decahydrate (Na₂CO₃·10H₂O). However, this is not what is referred to as soda ash.

5. **Conclusion**: Therefore, soda ash is specifically sodium carbonate (Na₂CO₃) and is used in various applications, including glass manufacturing, water treatment, and as a cleaning agent.

### Final Answer:
Soda ash is sodium carbonate, with the chemical formula Na₂CO₃.

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