Solid phosphorus pentachloride behaves as an ionic compound. Explain

Explanation

`PCl_(5)` conducts electricity in the molten state. This means that in the solid state it exists as `[PCl_(4)]^(+) [PCl_(6)]^(-)` in which the cation is tetrahedral and the anion is octahedral
`2PCl_(5) to `[PCl_(4)]^(+) [PCl_(6)]^(-)`
On melting, these ions become free to move and hence `PCl_(5)` conducts electricity in the molten state.