Periodicity
A. Periodic Table
- Comprehensive Periodic Table http://ptable.com/
- Evolution of Mendeleev's periodic table https://www.youtube.com/watch?v=O-48znAg7VE
B. Periodic Trend
- Halogen Displacement Reaction Animation http://www.bbc.co.uk/schools/gcsebitesize/science/edexcel_pre_2011/patterns/groupsrev5.shtml
- Ionic radius Animation http://ibchem.com/IB16/05.22.htm#a4