The shapes PCl_{4}^{+},PCl_{4}^{-} and AsC{{l}_{5}} are respectively:A. square planar, tetrahedral and see-sawB. tetrahedral, see-saw and trigonal bipyramidalC. tetrahedral, square planar and pentagonal bipyramidalD. trigonal bipyramidal, tetrahedral and square pyramidal

To determine the shapes of these molecules, we can use VSEPR (Valence Shell Electron Pair Repulsion) theory, which predicts molecular geometries based on the repulsions between electron pairs around a central atom. Here's the breakdown for each molecule:

PCl₄⁺ (Phosphorus tetrachloride cation):
Phosphorus (P) has 5 valence electrons and 4 bonding pairs, resulting in a steric number of 4. According to VSEPR theory, this leads to a tetrahedral geometry.

PCl₄⁻ (Phosphorus tetrachloride anion):
Similar to the cation, phosphorus (P) has 5 valence electrons and 4 bonding pairs, resulting in a tetrahedral geometry.

AsCl₅ (Arsenic pentachloride):
Arsenic (As) has 5 valence electrons and 5 bonding pairs, leading to a steric number of 5. This results in a trigonal bipyramidal geometry.

So, the correct answer is:

B. tetrahedral, see-saw, and trigonal bipyramidal