Which of the following statements are true for group `2` elements?

Options

A. Lattice enthalpy of oxides, carbonates, fluorides decreases form `Be` to `Ba`.
B. All form nitrides in air.
C. The solubility of the hydroxides increases from `Be` toe `Ba`.
D. All are correct.

Explanation

To determine which statements are true for group 2 elements (alkaline earth metals), we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Statement A: Lattice enthalpy of oxides, carbonates, and fluorides decreases from beryllium to barium.**
- **Analysis:** Lattice enthalpy is influenced by the charges of the ions and the distance between them. As we move down the group from beryllium to barium, the size of the cation increases (the radius of the cation increases). Since the anionic size remains relatively constant, the distance between the cation and anion increases, leading to a decrease in lattice enthalpy.
- **Conclusion:** This statement is **true**.

2. **Statement B: All alkaline earth metals form nitrides in air.**
- **Analysis:** Alkaline earth metals react with nitrogen to form nitrides. The general formula for the nitride formed by alkaline earth metals is M₃N₂, where M represents the metal. This reaction occurs for all alkaline earth metals.
- **Conclusion:** This statement is **true**.

3. **Statement C: The solubility of hydroxides increases from beryllium to barium.**
- **Analysis:** As we move down the group, the basicity of hydroxides increases due to the larger size of the cations, which leads to an increase in solubility. Barium hydroxide is more soluble than beryllium hydroxide.
- **Conclusion:** This statement is **true**.

4. **Final Conclusion:**
- Since all three statements (A, B, and C) are true, the correct answer is that all statements are true.

### Final Answer:
All the statements regarding group 2 elements are **true**.

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