Alkenes

Theory

Alkenes are hydrocarbons with carbon-carbon double bonds. They are also known as olefins since ethene, the first member of the homologous series forms oily liquid substance when treated with halogens. Ethene, the simplest alkene, is the largest-volume industrial organic compound. It is used to make polyethylene and a variety of other industrial and consumer chemicals. Alkenes polymerises to give many important polymers.

Structure and bonding in Alkenes :

• Alkenes are unsaturated hydrocarbons having at least one double bond. 
• They are represented by general foumula (G.F.) C_nH_2n (one double bond).
• In ethene C = C bond length is 1.34 Ã… and its bond energy is 146 kcal. mol^-1. 
• The hybridization of (C = C) alkenic carbon is sp².
• The  Ï€-e^– cloud is present above and below the plane of s-bonded skeleton.