Question

Why benzene is not called hexene though it has 6 carbon atoms.

Answer 1

mainly there are two types of HYDROCARBONS---------------
(i) ALIPHATIC
(ii) AROMATIC
ALIPHATIC HYDROCARBONS--------------- these are hydrocarbons containing C & H
& C-C are joined by single bond Or by double bonds OR by triple bonds----------
e.g. CH3 -CH2-CH3 OR H3 C- CH2- CH= CH2 OR H C=_ CH OR
(a) SINGLE BOND----------- ALKANE
(b) DOUBLE BOND ------------ ALKENE
(c) TRIPLE BOND------------- ALKYNE
now hexene are hydrocarbon containing ONE double bond such as --------------
CH3 -CH2-CH2-CH2 -CH = CH2 ( 1- HEXENE )
CH3 -CH2-CH2-CH= CH -CH3 ( 2- HEXENE )
CH3 -CH2 CH= CH - CH2- CH3 ( 3- HEXENE )
{CH3}2 - C= CH-CH2-CH3 ( ISO HEXENEOR 2-METHYL-2-PROPENE) AN SO ON
while aromatic hydrocarbons are compounds of C & H containing 6 C joined by
alternative double & single bonds inn closed chain ie. RING
so in benzene there are six C& 6 H joined by alternative double & single bonds
SO BENZENE HAS THREE DOUBLE BONDS & THREE SINGLE BONDS IN
CLOSED CHAIN LIKE A RING.
For this reason in spite of having 6 carbons benzene is not called hexene.