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periodictable.com

the definitive online periodic table reference site including technical data, and photographs and descriptions of thousands of samples of the chemical elements.

ptable.com

Interactive periodic table showing names, electrons, and oxidation states. Visualize trends, 3D orbitals, isotopes, and mix compounds. Fully descriptive writeups.

pubchem.ncbi.nlm.nih.gov

PubChem is the world's largest collection of freely accessible chemical information. Search chemicals by name, molecular formula, structure, and other identifiers. Find chemical and physical properties, biological activities, safety and toxicity information, patents, literature citations and more.

environmentalchemistry.com

this site provides chemistry, environmental and hazardous materials news, careers & resources including: in depth articles; a detailed periodic table of elements; chemical database; hazmat emergency response guides; hazmat placarding information; and much more.

wiredchemist.com

the wired chemist is an online collection of scientific resources, including databases, tutorials and animations.

lenntech.com

lenntech designs, builds and installs a wide range of odour treatment, water purification and air filtration products using uv, ozone, ecosorb, drum filtration. also cooling towers.

americanelements.com

American Elements: The Materials Science Company™ | Certified bulk & lab quantity manufacturer & supplier of metals, chemicals, nanoparticles & other advanced materials.

chemlin.org

chemlin.org website about chemistry and chemical substances.

knowledgedoor.com

Our periodic table has over 25000 facts covering all chemical elements and spanning more than 130 quantities. Each table entry has a full citation identifying its source. Our units and constants handbook features descriptions of the 391 units and 74 constants supported by our unit conversion calculators.