aromatics?

Question

are all aromatic compounds cyclic?

Answer 1

Yes. Aromatic compounds have to obey the following criteria:

They must have
1. A delocalized conjugated π system, most commonly an arrangement of alternating single and double bonds
2.Coplanar structure, with all the contributing atoms in the same plane
3. Contributing atoms arranged in one or more rings
4. A number of π delocalized electrons that is even, but not a multiple of 4. This is known as Hückel's rule(4n-2). Permissible numbers of π electrons include 2, 6, 10, 14, and so on
5.Special reactivity in organic reactions such as electrophilic aromatic substitution and nucleophilic aromatic substitution

Answer 2

Actually yes they must be cyclic but they do not need to be planar as the answer above says. The fullerenes are not planar (in fact spheriodal) but are very much aromatic.

Answer 3

All Aromatics are Cyclic and are based on the Benzene Ring.
Examples:
The 'Xylenes' consist of 3 isomers each based on the Benzene ring and have two Methyl Groups replacing two Hydrogens in the ring.
1...1,2-Dimethylbenzene. ( The 2 methyls are replacing Hydrogen in Carbons 1 and 2 in the ring and is called...
'Ortho-Xylene' (o-xylene).
2...1,3-Dimethylbenzene. (Methyls at Carbons 1 and 3 in the ring and is called...Meta-xylene (m-xylene).
3...1,4-Dimethylbenzene. Methyls at Carbons 1 and 4 in the ring and is called...Para-xylene (p-xylene).
Each of the above have the same formula of C6H4(CH3)2 but with the ' o-', ' p-' or ' m- ' as a prefix.
Ethylbenzene is a Benzene ring with a side chain of Ethylene (Ethene) replacing a Hydrogen.
(Also called 'Styrene' or 'Vinyl-benzene'). C6H5CH=CH2.

Answer 4

Yes!!!!
Aromatic - cyclic
Aliphatic - linear.

Answer 5

yes.. all aromatics are cyclic..

Answer 6

Yes, but some of them have quite complex multiple ring structures

Answer 7

yes

Answer 8

yes