Organic chemistry:
IUPAC Recommendations on Organic & Biochemical Nomenclature
You can search the database or choose a subject for recommendations on the proper naming of organic compounds.
Physical chemistry:
Kaye & Laby Tables of Physical and Chemical Constants
The entire, unedited contents of the 16th edition (1995), containing tables of data, formulae, graphs and charts. Topics from fundamental constants to fibre optics, superconductivity to Raman spectroscopy, etc. Contents will be regularly reviewed and updated at the (UK) National Physical Laboratory.
Biochemistry:
Classical, Quantum, Nanoscale & Statistical Thermodynamics & Mechanics Data and Property Calculation Sites on the Web
A large listing of internet sites for property calculations. From the Thermodynamics Research Lab, the University of Illinois at Chicago.
NIST Chemistry WebBook
Physical and thermophysical properties - mostly organic compounds.
SDBS - Integrated Spectral Data Base System for Organic Compounds
Search for mass, NMR, FT-IR, laser Raman and ESR spectral data for organic compounds. From the National Institute of Advanced Industrial Science and Technology Tsukuba, Ibaraki, Japan.
Thermodex
Index to selected thermodynamic data handbooks that contain property data.
Chemical Synthesis Database
A searchable database of chemical substances which gives the chemical structure, density, boiling & melting point, CAS registry
American Chemical Society
The American Chemical Society (ACS) is a scientific society based in the United States that supports scientific inquiry in the field of chemistry.
Chemical Abstract Service
Chemical Abstracts Service (CAS) is a division of the American Chemical Society. It is a source of chemical information.
Chemical Heritage Society
The Chemical Heritage Foundation (CHF) is an institution for the history of science.
International Union of Pure and Applied Chemistry
The world authority on chemical nomenclature, terminology, standardized methods for measurement, atomic weights and other critically evaluated data.
Nobelprize.org
The official web site of the Nobel Prize
Nobel Prize Internet Archive
A comprehensive list of Nobel Peace Prize Laureates.
Royal Society of Chemistry
The Royal Society of Chemistry (RSC) is a professional association in the United Kingdom with the goal of "advancing the chemical sciences."
Resources for Chemistry Educators
Link to instructional software can be found in the list on the right-hand side.
WWW Chemistry Guide--Software
A list of chemistry software both commercial & non-commercial.