Which of the following is not an ionic halide ?

Options

A. `UF_4`
B. `PbCl_2`
C. `SnCl_2`
D. `UF_6`

Answer

To determine which of the following compounds is not an ionic halide, we need to analyze the nature of each compound provided: UF4, PbCl2, SnCl2, and UF6.

### Step-by-Step Solution:

1. **Understanding Ionic Halides**: Ionic halides are compounds formed from the electrostatic attraction between cations and anions. They typically consist of a metal cation and a halide anion. The presence of covalent character in a compound can indicate that it is not purely ionic.

2. **Analyzing the Compounds**:
- **UF4 (Uranium Tetrafluoride)**: Uranium is a highly charged cation (U^4+), and fluorine is a small, highly electronegative anion. The high charge and small size of the cation can lead to significant polarization of the anion, resulting in some covalent character. However, UF4 is generally considered to have ionic character.

- **PbCl2 (Lead(II) Chloride)**: Lead in PbCl2 has a +2 oxidation state. While it can exhibit some covalent character, PbCl2 is primarily ionic due to the lower oxidation state of lead.

- **SnCl2 (Tin(II) Chloride)**: Similar to PbCl2, SnCl2 has a +2 oxidation state for tin. It also exhibits ionic character, although it can have some covalent character.

- **UF6 (Uranium Hexafluoride)**: In UF6, uranium is in a +6 oxidation state. The high charge and the presence of multiple fluorine atoms lead to significant covalent character due to the polarization of the anions. This makes UF6 primarily covalent rather than ionic.

3. **Conclusion**: Among the given options, UF6 is the compound that exhibits significant covalent character and is therefore not classified as an ionic halide. The other compounds (UF4, PbCl2, and SnCl2) are primarily ionic halides.

### Final Answer:
**UF6 is not an ionic halide.**