What is the change in hybridization (if any) of the Al atom in the following reaction.
`AlCl_3 + Cl^(-) to AlCl_4^(-)`

Explanation

E.C. of `._(13)Al = 1s^(2) 2s^(2) 2p^(6) 3s^(2) 3p_(x)^(1)` (Ground state ) or = `1s^(2) 2s^(2) 2p^(6) 3s^(1) 3p_(x)^(1) p_(y)^(1)` (Excited state ).