# Sodium and caesium are both Group I metals. Compare the physical and chemical properties of sodium and caesium, referring to trends in Group I.

> Cambridge International IGCSE Chemistry (0620) — 8.2 Group I properties · Compare · 4 marks

## Mark scheme (4 marks)

1. Caesium has a lower melting point than sodium / melting points decrease down Group I
2. Caesium is less dense / softer than sodium OR caesium has a lower density than sodium (accept: density decreases down Group I / caesium is softer)
3. Caesium is more reactive than sodium / reactivity increases down Group I
4. Both / caesium reacts with water to produce a hydroxide and hydrogen / caesium reacts more vigorously with water than sodium

## Key terms

- [Group I](https://www.gradenine.co.uk/glossary/group-i)

## Related

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Source: [GradeNine](https://www.gradenine.co.uk/q/sodium-and-caesium-are-both-group-8ee586e9) · Published by Druglandscape Ltd.