Arsenic Pentachloride Shape

Arsenic pentachloride (AsCl5) has a trigonal bipyramidal shape. This means that it has five chlorine atoms bonded to the central arsenic atom, arranged in a way that resembles an octahedron with two opposite corners missing.

The two positions where the corners are missing are called axial positions, and the other three positions where the chlorine atoms lie on the same plane are called equatorial positions. The axial positions are located along the vertical axis of the molecule, while the equatorial positions are located in a horizontal plane.

In the trigonal bipyramidal shape, the bond angles between the axial chlorine atoms and the central arsenic atom are 90 degrees, while the bond angles between the equatorial chlorine atoms and the central arsenic atom are 120 degrees. This arrangement of electron pairs around the central atom minimizes the repulsion between them and maximizes the stability of the molecule.

Overall, the trigonal bipyramidal shape of arsenic pentachloride arises from the interaction of the five electron pairs around the central arsenic atom, which give rise to the unique arrangement of the molecule's five chlorine atoms.