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Description

Two presenters use animations of atoms in the periodic table to explain that elements are arranged according to their size. Mass and atomic numbers are referred to, but not explained. The concept of groups in the periodic table is explained using animations of electrons. The similarity in reactivity of elements in groups is mentioned.
This clip is from:
First broadcast:
21 November 2008

Classroom Ideas

This clip could be used to introduce the concept of groups in the periodic table. After watching it, students could be asked to work in groups to explain what they have learned about the properties of different groups. Ask them to identify any changes that occur as you move down the group.