Question

How many carbons are in the planar double-bond system of 3-methylcyclopentene?

Answer 1

There are a total of four (4) carbon that are in the planar double-bond system of 3-methylcyclopentene. The 3-methylcyclopentene can be found in spices and herbs, it is also a constituent of the flowers of Jasminum sambac (Arabian jasmine). It is also belongs to the family of Aliphatic Homomonocyclic Compounds.

Answer 2

There are a total of four (4) carbon that are in the planar double-bond system of 3-methylcyclopentene.

Of the five carbons in the cyclopentene, 1 carbon is attached with CH3 group while the other 4 are attached with H atoms which are in the same plane as of double bond. The carbon of the cycle attached with CH3 group are not in same plane as the rest of the carbon  of cyclopentene.