`AlCl_3` in water at pH < 7 forms

Options

A. tetrahedral `Al(OH)_(4)^(-)` ions
B. octahedral `Al(OH)_(6)^(3-)` ions
C. square planar `Al(OH)_(4)^(-)` ions
D. octahedral `Al(OH_2)^(6)^(3+)` ions

Answer

D

Explanation

`AlCl_3` from `[Al(H_2O)_6]^(3+)` in water due to acidic medium (pH < 7) .
`AlCl_3 + 6H_2O to [Al(H_2O)_6]^(3+) + 3Cl`