Chemistry · Hydrocarbons
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Which of the following elements is needed to add in the given diagram to make it aromatic benzene?

- A
-H
- B
-OH
- C
-CH
- D
-H2
There is -H missing on one of the carbon atoms to make it a benzene ring.
The addition of a single hydrogen atom (-H) is necessary to satisfy the valency of a carbon atom, completing the structure of an aromatic benzene ring.
An -OH group would alter the structure of the benzene ring, forming phenol instead, which is not required here.
Adding a -CH group would disrupt the aromatic nature of benzene, leading to a different compound altogether.
The addition of H2 is unnecessary and would result in an excess hydrogen, disrupting the aromatic stability of benzene.
Tagged under Chemistry · Hydrocarbons · 2016