$sp^3$ hybridization leads to which shape of the molecule?

When $BCl_3$ is treated with water,it hydrolyses and forms $[B(OH)_4]^-$ only,whereas $AlCl_3$ in acidified aqueous solution forms $[Al(H_2O)_6]^{3+}$ ion. Explain what are the hybridizations of boron and aluminum in these species?

Explain the directional properties of bonds using $VB$ theory.

The shape of $CH_3^+$ species is

The correct order of increasing $s$-character (in percentage) in the hybrid orbitals of the following molecules/ions is: $(I) \, CO_3^{2-}$,$(II) \, XeF_4$,$(III) \, I_3^-$,$(IV) \, NCl_3$,$(V) \, BeCl_2$.

The hybridisation of the central atom in $NF_3$ is: