# Explain why iodine (I₂) is a solid at room temperature but does not conduct electricity in any state.

> Cambridge International IGCSE Chemistry (0620) — 2.5 Simple molecules and covalent bonds · Explain · 4 marks

> Iodine is a shiny, grey-purple solid at room temperature. It is a simple molecular substance made up of I₂ molecules.

## Mark scheme (4 marks)

1. Iodine molecules are held together by weak intermolecular forces
2. These weak intermolecular forces are strong enough to keep the molecules in a fixed arrangement / together as a solid at room temperature
3. There are no free / mobile electrons (or ions) in iodine
4. Electrical conductivity requires charged particles that can move / flow, so iodine cannot conduct in any state

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