Which does not exists in solid state

Options

A. `LiHCO_(3)`
B. `CaCO_(3)`
C. `NaHCO_(3)`
D. `Na_(2)CO_(3)`

Explanation

To determine which compound does not exist in solid state among the given options (LiHCO3, CaCO3, NaHCO3, Na2CO3), we can analyze each compound based on their properties and behavior.

### Step-by-Step Solution:

1. **Understanding the Compounds**:
- **LiHCO3 (Lithium bicarbonate)**: This is a bicarbonate salt of lithium.
- **CaCO3 (Calcium carbonate)**: This is a carbonate salt of calcium.
- **NaHCO3 (Sodium bicarbonate)**: This is a bicarbonate salt of sodium, commonly known as baking soda.
- **Na2CO3 (Sodium carbonate)**: This is a carbonate salt of sodium, also known as soda ash.

2. **Analyzing Solid State Existence**:
- **LiHCO3**: Lithium bicarbonate is known to be unstable and tends to decompose into lithium carbonate and carbon dioxide when heated. It is also highly soluble in water, which suggests that it does not have a stable solid state under normal conditions.
- **CaCO3**: Calcium carbonate is a stable compound that exists in solid state and is commonly found in nature (e.g., limestone).
- **NaHCO3**: Sodium bicarbonate is also stable and exists in solid state, widely used in cooking and as a leavening agent.
- **Na2CO3**: Sodium carbonate is a stable solid compound used in various applications, including glass manufacturing.

3. **Conclusion**:
- Among the given options, **LiHCO3** does not exist in solid state due to its high solubility and tendency to decompose. The other compounds (CaCO3, NaHCO3, and Na2CO3) are stable and exist as solids.

### Final Answer:
**LiHCO3 does not exist in solid state.**