# Explain why the metallic character of elements increases down Group 1 of the periodic table.

> IB DP Chemistry Standard Level (2023 syllabus) — S3.1 The periodic table: classification of elements · Explain · 4 marks

## Mark scheme (4 marks)

1. Going down Group 1, the number of electron shells (energy levels) increases.
2. The outer (valence) electron is further from the nucleus, so the atomic radius increases.
3. There is increased shielding/screening of the outer electron by inner electron shells, reducing the effective nuclear charge experienced by the valence electron.
4. The outer electron is therefore more easily lost, giving a lower ionisation energy, which is characteristic of greater metallic behaviour.

## Key terms

- [metallic character](https://www.gradenine.co.uk/glossary/metallic-character)

## Related

- [Revision notes for IB DP Chemistry Standard Level (2023 syllabus)](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)

---
Source: [GradeNine](https://www.gradenine.co.uk/q/explain-why-the-metallic-character-of-6c507e97) · Published by Druglandscape Ltd.