Why does graphite conduct electricity?
Graphite conducts electricity because each carbon atom has one delocalised electron that is free to move and carry charge.
GCSE Chemistry
Written & reviewed by James Millett — Biology (Imperial College London), PGCE Science (University of Cambridge).
In more detail
In graphite each carbon atom forms only three covalent bonds, leaving one outer electron per atom delocalised. These delocalised electrons can move freely along the layers, so they carry charge — allowing graphite to conduct electricity (and heat). Diamond, where every carbon forms four bonds, has no free electrons and does not conduct.
Key points for the exam
- Each carbon forms 3 bonds → 1 delocalised electron per atom.
- Delocalised electrons move along the layers and carry charge.
- Graphite is a non-metal that conducts — a favourite exam contrast with diamond.
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