Online Thermodynamic and
Physico-Chemical Data (all free)

Elements:
WebElements
	- various free data from the periodic table of elements including chemical data, ionization enthalpies, and much more; Mark Winter, University of Sheffield, UK. (WebElements is one of most popular of many links to periodic tables.)
Compounds:
Compound-Web
	- list of the pure substances in the F*A*C*T compound database; CRCT École Polytechnique, Montréal, Québec, Canada.
CODATA Thermodynamic Values
	- for the properties of approximately 150 key chemical substances, International Council of Scientific Unions CODATA ;Committee on Data for Science and Technology.
CS ChemFinder Chemical Searching and Information Integration
	- a useful tool where the user gives one or more of compound name, formula, formula weight and/or CAS RN and ChemFinder fills in the blanks and also returns other properties for over 40,000 compounds with links to other sites; CambridgeSoft Corporation, Cambridge, MA, USA.
GRI-Mech
	- thermodynamic database (Delta H(298K), S(298K), Cp(298K)) for approx. 50 species including nitrogen based species; Bob Serauskas et al, Gas Research Instiutute, Chicago, Il, USA.
MELTS
	- software including free thermodynamic data on several common pure mineral solids and the MELTS Supplemental Calculator; Mark S. Ghiorso et al, Geological Sciences, University of Washington, Seattle, USA.
NEA Data Bank
	- including NEA TDB thermodynamic data bank (Delta H(298K), S(298K), Cp(T)) for various compounds of the most important elements present in high-level radioactive waste, namely U, Tc, Np, Pu, Am; Nuclear Energy Agency, France.
NIST
	- Standard References Data Program, including the Chemistry WebBook for free thermodynamic data (Delta H(298K), S(298K), Cp tables) for over 5000 compounds, heats of reaction data for over 3000 reactions, and ion energetics data for over 14000 compounds; Malcolm W. Chase, Gaithersburg, MD, USA.
Technion
	- thermodynamic ideal gas data in polynomial form for combustion and air pollution containing about 800 compounds of mainly organic molecules and radicals C1 to C70 and aditional compounds including some solid and liquid species; Alexander Burcat, Aerospace Eng., Technion-Israel Inst. of Technology, Haifa, Israel.
Solutions:
MELTS
	- software including free thermodynamic data on multicomponent liquid silicate melts and approx. 15 common mineral solids solutions ; Mark S. Ghiorso et al, Geological Sciences, University of Washington, Seattle, USA.
Water/steam/aqueous:
JESS
	- thermodynamic database of complex aqueous equilibria, featuring thousands of primitive species symbols, composite species symbols, chemical names and CAS Registry numbers; Peter M May, Murdoch University, Western Australia.
MELTS
	- software including free thermodynamic data on water ; Mark S. Ghiorso et al, Geological Sciences, University of Washington, Seattle, USA.
Fundamental constants:
Atomic Weights of the Elements
	- IUPAC Commission on Atomic Weights and Isotopic Abundances, 1993; IUPAC International Union of Pure and Applied Chemistry.
Table of the Nuclides
	J. Chang, Korea Atomic Energy Research Institute.
CODATA Recommended Values of the Fundamental Physical Constants including Physico-Chemical Constants
	Physics Laboratory, NIST, Gaithersburg, MD, USA.
Conversion Factor Table
	Peter Wallin, University of Wisconsin Oshkosh, WI, USA.
NPL
	- fundamental constants and energy conversion factors; National Physics Laboratory, Teddington, Middlesex, UK.