organic chemistryWatch this thread
can someone explain the difference in bonding orbitals of carbon atoms in butane and butene.
In butene, there is a C=C present. this happens when an electron is promoted from the 2s orbital to the 2p orbital so there are 4 unpaired electrons in 2s/p. Three of the electrons in the 2s/p are bonded, leaving one unpaired electron in the 2p orbital of each carbon and the orbitals containing the unpaired electrons in each carbon overlap each other above and below the C=C. This is pi bonding.