Draw the orbital picture of following molecules: Methane (CH4)
Carbon has two half-filled orbitals in ground state (1s2, 2s2, 2px 1 2py 1, 2pz 0). It has four half-filled orbitals in excited state since one electron is promoted from 2s to empty 2p orbital during chemical combination (1s2, 2s2, 2px 1 2py 1, 2pz 0)
Now one 2s and three 2p orbitals undergo sp3 hybridization to form four sp3 hybrid orbitals of equivalent energy and identical shape and size which takes tetrahedral geometry with bond angle 109.28º.
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