You need to have JavaScript enabled to view this video clip.

Description

Three-dimensional animations of atoms in the periodic table explain that elements in the same period have the same number of shells (or orbits). A summary of groups in the periodic table is given at the end.
This clip is from:
First broadcast:
21 November 2008

Classroom Ideas

This clip could be used to explain that elements in the same period have the same number of shells (or orbits). Ask students to investigate changes to reactivity related to moving down a group and explain in their own words why this changes.