the difference between pi bonds and sigma bonds
A sigma bond is the end-to-end overlap of the bonding orbitals, usually hybrid orbitals. The sigma bond is a single bond. A pi bond is the side-to-side overlap of unhybridized p-orbitals. A pi bond, along with a sigma bond form a double bond. sigma bond is used in hybridization but pi bond when dealing with saturated molecules is not used,that is double bonds.The oygen molecule is sp hybridized have you ever reasoned or found out why.
In organic chemistry sigma bonds (Ï) are always the first bond between two atoms, resulting from overlap along the bonding axis (of hybrid orbitals), while pi bonds (Ï) are second and third bonds resulting from the overlap of p orbitals, above and below (or in front and back of) the bonding axis.