Question

The hybridised state of ${Al}^{3+}$ in the complex ion formed when $Al{Cl}_3$ is treated with aqueous acid is:

• A. ${sp}^3$
• B. ${dsp}^2$
• C. ${sp}^3{d}^2$
• D. ${sp}^{2}d$
• E. ${sp}^2$

Answer 1

The correct option is C ${sp}^3{d}^2$

$A{l}^{3+}$ aqueous acid $\to {\left[Al{\left(H_{2}O\right)}_6\right]}^{3+}$.

${Al}^{3+}$ ions give a complex ion in which ${Al}^{3+}$ ion form six coordinate covalent bonds with six $H_{2}O$ molecules.

Hence, it shows ${sp}^3{d}^2$ hybridisation.

(Due to availability of vacant $3d$-orbitals.)

$Al=3s^{2}3p^1$

${Al}^{3+}=3s^0$

Four electron pairs denoted by $6H_{2}O$ molecules.