Which statement about graphite is correct?
Answer and explanation
Correct answer: A. It conducts electricity because each carbon atom has a delocalised electron between its layers
- Step 1: In graphite each carbon atom bonds to three others in layers.
- Step 2: The fourth outer electron is delocalised and free to move, so graphite conducts.
Answer
It conducts electricity because each carbon atom has a delocalised electron between its layers.
Why not the others: It conducts electricity because it contains free ions: graphite contains no ions. It is hard because each carbon atom forms four covalent bonds: this describes diamond; graphite carbon atoms form three bonds. It has a low melting point because it has weak covalent bonds: the covalent bonds in graphite are strong and its melting point is very high.
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