Alkenes are unsaturated hydrocarbons that contain a carbon-carbon double bond functional group. Ethylene (C2H4) is an example alkene. The carbon atoms in alkenes adopt sp2 hybridization, resulting in a flat structure with 120 degree bond angles between atoms. An alkene's double bond consists of one sigma bond and one pi bond between the carbon atoms, restricting rotation about the double bond.

1. Alkenes
By
Dr. NIDHI GUPTA
M.M. College of Pharmacy
Mullana, Ambala,
Haryana, India

2. Alkenes CnH2n “unsaturated” hydrocarbons
C2H4 ethylene
Functional group = carbon-carbon double bond
sp2 hybridization => flat, 120o bond angles
σ bond & π bond => H2C=CH2
No rotation about double bond!
C C
H
H H
H