Which is correct in increasing order of ionic character ?

Options

A. `AlCl_(3) lt MgCl_(2) lt NaCl`
B. `LiI lt LiBr lt LiCl`
C. `NaCl gt MgCl_(2) lt AlCl_(3)`
D. None of the above

Explanation

To determine the increasing order of ionic character among the given compounds, we need to analyze the factors that influence ionic character, such as the size of the ions, the charge on the ions, and the polarization effect.

### Step-by-Step Solution:

1. **Understanding Ionic Character**: Ionic character refers to the extent to which a bond between two atoms has ionic characteristics. It is influenced by the size of the ions and their charges.

2. **Analyzing the First Option**:
- The first option presents three compounds: AlCl3, MgCl2, and NaCl.
- We need to consider the cation sizes: Na+ (larger) > Mg2+ (smaller) > Al3+ (smallest).
- Smaller cations have a higher charge density, which leads to greater polarization of the anion, resulting in more covalent character.
- Therefore, we can conclude that:
- AlCl3 has the least ionic character (most covalent) due to the small size of Al3+.
- MgCl2 has a moderate ionic character.
- NaCl has the highest ionic character due to the larger Na+ ion.

3. **Arranging the First Option**:
- The order of ionic character from least to most is:
- AlCl3 < MgCl2 < NaCl

4. **Analyzing the Second Option**:
- The second option presents LiI, LiBr, and LiCl.
- According to Fajan's rules, the polarizing power of cations is inversely related to their size. Li+ is small and has a high polarizing power.
- As the size of the anion increases (I- < Br- < Cl-), the covalent character increases, leading to a decrease in ionic character.
- Therefore, we can conclude that:
- LiI has the most covalent character (least ionic).
- LiBr has moderate ionic character.
- LiCl has the highest ionic character.

5. **Arranging the Second Option**:
- The order of ionic character from least to most is:
- LiI < LiBr < LiCl

6. **Final Conclusion**:
- Based on the analysis, we find that both options A and B are correct in terms of increasing order of ionic character.

### Final Answer:
- The correct increasing order of ionic character is:
- For the first option: AlCl3 < MgCl2 < NaCl
- For the second option: LiI < LiBr < LiCl