Which of the following contains an sp2-hybridized carbon?

CH4
CH3-
CH3CH3
CH3+
HC(triple bond)CH

Best Answer - Chosen by Voters
It is CH3+
There are 3 pairs of electrons around the carbon atom.
This suits the sp2 hybridised orbitals of carbon and it will take the shape of trigonal planar.

CH3- is not sp2 hybridised.
It is sp3 hybridised.
There are 4 pairs of electrons around the carbon atom.

Although it is sp3 hybridised, the shape is trigonal pyramidal because there is a lone pair of electrons.