# Benzene is described as an aromatic compound. Explain the bonding in benzene and describe two properties that arise from its aromatic nature.

> WJEC A-Level Chemistry (Wales) — 4.2 Aromaticity · Explain · 5 marks

> Benzene has the molecular formula C₆H₆ and was originally thought to contain alternating single and double carbon–carbon bonds. However, experimental evidence shows that all carbon–carbon bonds in benzene are identical in length and that benzene is less reactive than expected for a molecule containing double bonds.

## Mark scheme (5 marks)

1. Benzene contains a ring of six carbon atoms
2. The electrons are delocalised / spread over the whole ring (rather than fixed between two carbon atoms)
3. All carbon–carbon bond lengths in benzene are equal / the same (intermediate between a single and a double bond)
4. Benzene is more stable / less reactive than expected (compared to a molecule with localised double bonds / compared to cyclohexadiene)
5. Benzene undergoes electrophilic substitution rather than addition (in order to preserve the stable delocalised ring)

## Key terms

- [aromatic](https://www.gradenine.co.uk/glossary/aromatic)

## Related

- [Revision notes for WJEC A-Level Chemistry (Wales)](https://www.gradenine.co.uk/learn)
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Source: [GradeNine](https://www.gradenine.co.uk/q/benzene-is-described-as-an-aromatic-689b7c4e) · Published by Druglandscape Ltd.