Discuss in detail about the general methods of preparation of alkenes.

Explanation

Preparation of ethane by kolbe's electrolytic method :
When an aqueous solution of potassium succinate is electrolyzed between two platinum electrodes,ethene is produced at the anode.
`underset(CH_(2)*COOK)overset(CH_(2)*COOK)(|)overset("Electrolysis")(to)overset(CH_(2)*COO^(-))underset(CH_(2)*COO^(-))(|)+2K^(+)`
Potassium Succinate
At node
`overset(CH_(2)*COO^(-))underset(CH_(2)*COO^(-))(|)tounderset("Ethene")underset(CH_(2))overset(CH_(2))(||)+CO_(2(g))+2e^(-)`