The Visual Elements Periodic Table -
Chemsoc
http://www.rsc.org/chemsoc/visualelements/pages/pertable_j.htm
General Chemistry Online – Fred Senese
http://antoine.frostburg.edu/chem/senese/101/index.shtml
Chemical Achievers:
The Human Face of the Chemical Sciences
http://www.chemheritage.org/classroom/chemach/gases/index.html
The
Wooden Periodic Table Table – Theodore Gray
http://www.theodoregray.com/PeriodicTable/
chemguide – Jim
Clark
http://www.chemguide.co.uk/
Intute:
Science, Engineering and Technology - Chemistry
EXCELLENT advanced search feature!
http://www.intute.ac.uk/sciences/chemistry/