Answer:
1
Explanation:
Trigonal planar geometry is shown by the compounds where hybridization of central atom is [tex]sp^2[/tex].
In [tex]sp^2[/tex] hybridization, three hybrid orbitals are equally spaced at an angle of 120°.
Some of the compounds having [tex]sp^2[/tex] hybridization are [tex]CO_3^{2-}[/tex], [tex]SO_3[/tex], etc
In [tex]sp^2[/tex] hybridizationm, one s-orbital and 2 p-orbitals are involved.
Total no. of orbitals present in p-subshell is 3.
As 2 is involved in [tex]sp^2[/tex] hybridization, therefore no. of unhybridized orbital in [tex]sp^2[/tex] hybridization is 1.
