Chlorine

ChemGlobe: Chlorine - Electronic, thermal, and steric data along with basic information.
partisans.spurious.biz/~pkremer/projects/chemglobe/ptoe/_/17.html

ChemicalElements.com: Chlorine - Basic information, atomic structure, and isotopes.
www.chemicalelements.com/elements/cl.html

Chlorine Online - Information about chlorine and its derivatives from Euro Chlor.
www.eurochlor.org

EnvironmentalChemistry.com: Chlorine - Atomic structure, chemical and physical properties, and table of nuclides.
environmentalchemistry.com/yogi/periodic/Cl.html

Especiál Gas Inc.: Chlorine - Numeric data, uses, and general information.
www.c-f-c.com/specgas_products/chlorine.htm

It's Elemental: Chlorine - Basic physical and historical information.
education.jlab.org/itselemental/ele017.html

LANL: Chlorine - History, properties, uses, and handling.
periodic.lanl.gov/elements/17.html

Lenntech: Chlorine - Physical data, chemical properties, health and environmental effects.
www.lenntech.com/Periodic-chart-elements/Cl-en.htm

Visual Elements: Chlorine - Image, animation, uses, biological role, and key isotopes.
www.chemsoc.org/viselements/pages/chlorine.html

Wikipedia: Chlorine - Properties of the element, including its history, applications, and characteristics.
en.wikipedia.org/wiki/Chlorine