Identify the reaction type

We are asked about the species formed on fluorination of $\mathrm{PCl_5}$ in a polar organic solvent.

In polar solvents, phosphorus pentachloride behaves as an ionic species: $\mathrm{PCl_5 \rightleftharpoons [PCl_4]^+ [PCl_6]^-}$

On fluorination, fluorine substitutes chloride stepwise, and mixed halo-phosphorus ionic species are formed.

Known behavior of fluorination of $\mathrm{PCl_5}$

Fluorination of $\mathrm{PCl_5}$ does not directly give only simple molecular products like $\mathrm{PF_5}$ or $\mathrm{PF_3}$ in polar organic medium.

Instead, due to ionic dissociation in such solvents, species such as: $[\mathrm{PCl_4}]^+[\mathrm{PCl_4F_2}]^-$ and $[\mathrm{PCl_4}]^+[\mathrm{PF_6}]^-$ are formed.

Check each option

Option A: $[\mathrm{PF_4}]^+[\mathrm{PF_6}]^-$ and $[\mathrm{PCl_4}]^+[\mathrm{PF_6}]^-$

• $[\mathrm{PCl_4}]^+[\mathrm{PF_6}]^-$ is known.
• But $[\mathrm{PF_4}]^+[\mathrm{PF_6}]^-$ is not the characteristic species formed in this fluorination of $\mathrm{PCl_5}$ in polar organic solvent.
• So this option is incorrect.

Option B: $[\mathrm{PCl_4}]^+[\mathrm{PCl_4F_2}]^-$ and $[\mathrm{PCl_4}]^+[\mathrm{PF_6}]^-$

• These are the standard ionic fluorination products observed in polar organic solvent.
• Hence correct.

Option C: $\mathrm{PF_3}$ and $\mathrm{PCl_3}$

• These would imply reduction/disproportionation products, not the expected fluorination products here.
• Incorrect.

Option D: $\mathrm{PF_5}$ and $\mathrm{PCl_3}$

• This is also not the correct description for fluorination in polar organic medium, where ionic species are stabilized.
• Incorrect.

Final conclusion

The correct species formed are: $[\mathrm{PCl_4}]^+[\mathrm{PCl_4F_2}]^- \quad \text{and} \quad [\mathrm{PCl_4}]^+[\mathrm{PF_6}]^-$

Therefore, the correct option is B.