# Explain why fluorine is more reactive than iodine, and describe the trend in boiling points as you go down Group 7.

> Edexcel GCSE Chemistry (1CH0) — 6.2 Group 7 · Explain · 4 marks

## Mark scheme (4 marks)

1. Fluorine is more reactive than iodine because fluorine's outer shell is closer to / smaller atomic radius than iodine's outer shell
2. So fluorine gains an electron more easily / attracts an incoming electron more strongly than iodine
3. Boiling points increase going down Group 7
4. So iodine has a higher boiling point than fluorine / chlorine / bromine (correct relative comparison stated)

## Key terms

- [boiling points](https://www.gradenine.co.uk/glossary/boiling-points)
- [Group 7](https://www.gradenine.co.uk/glossary/group-7)

## Related

- [Revision notes for Edexcel GCSE Chemistry (1CH0)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

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Source: [GradeNine](https://www.gradenine.co.uk/q/explain-why-fluorine-is-more-reactive-c1e4b451) · Published by Druglandscape Ltd.