Which of the following statement is not correct ?

Options

A. NaCl being an ionic compound is a good conductor electricity in the solid state.
B. In canonical structures there is no difference in the arrangement of atoms.
C. Hybrid form stronger bonds than pure orbitals.
D. VSEPR Theory can explain the square planar geometry of `XeF_4`

Explanation

To determine which of the following statements is not correct, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Statement 1**: "NaCl being an ionic compound is a good conductor of electricity in the solid state."
- **Analysis**: This statement is incorrect. In the solid state, NaCl forms a crystal lattice structure where Na⁺ and Cl⁻ ions are fixed in place and cannot move freely. Since electrical conductivity requires the movement of charged particles, NaCl cannot conduct electricity in the solid state. It can only conduct electricity when melted (molten state) or dissolved in water (aqueous state) because the ions are free to move in those states.

2. **Statement 2**: "There is no difference in the arrangement of atoms in resonance."
- **Analysis**: This statement is correct. In resonance structures, the arrangement of atoms remains the same; only the positions of the electrons (lone pairs and pi bonds) change. For example, in benzene, the carbon atoms remain fixed while the double bonds shift positions.

3. **Statement 3**: "Hybrid orbitals form stronger bonds than pure orbitals."
- **Analysis**: This statement is also correct. Hybrid orbitals have greater directional character and overlap more effectively than pure orbitals, leading to stronger bonds. The mixing of atomic orbitals to form hybrid orbitals results in bonds that are more stable.

4. **Statement 4**: "VSEPR theory can explain the square planar geometry of XeF4."
- **Analysis**: This statement is correct. According to VSEPR theory, the molecular geometry of XeF4 can be explained by considering the arrangement of bonding pairs and lone pairs around the central xenon atom. Xe has 8 valence electrons, forms 4 bonds with fluorine, and has 2 lone pairs, resulting in a square planar geometry.

### Conclusion:
The statement that is not correct is **Statement 1**: "NaCl being an ionic compound is a good conductor of electricity in the solid state."