Statement - I :Bond lengths of P–Cl bonds in gaseous PCl₅ and solid PCl₅ are not equal.
Statement - II :Because in solid state, two PCl₅ molecules are associated.

As in solid state, PCI₅ exists as an ionic solid [PCI₄]⁺[PCI₆]^- in which the cation, [PCI₄]⁺ is tetrahedral and the anion, [PCI₆]^- is octahedral. 

PCI₅ in gaseous state has trigonal bipyramidal structure in which three equatorial bonds are equivalent, while the two axial bonds are longer than equatorial bonds due to more bond pair repulsion.