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The list given in ISO 31-8:1992 was quoted from the 1998 IUPAC "Green Book" Quantities, Units and Symbols in Physical Chemistry and adds in some cases in parentheses the Latin name for information, where the standard symbol has no relation to the English name of the element. Since the 1992 edition of the standard was published, some elements ...
This glossary of chemistry terms is a list of terms and definitions relevant to chemistry, including chemical laws, diagrams and formulae, laboratory tools, glassware, and equipment. Chemistry is a physical science concerned with the composition, structure, and properties of matter , as well as the changes it undergoes during chemical reactions ...
The IUCR definition [2] used by crystallographers is: Two crystals are said to be isostructural, if they have the same structure, but not necessarily the same cell dimensions nor the same chemical composition, and with a 'comparable' variability in the atomic coordinates to that of the cell dimensions and chemical composition.
In chemistry, isomerization or isomerisation is the process in which a molecule, polyatomic ion or molecular fragment is transformed into an isomer with a different chemical structure. [1] Enolization is an example of isomerization, as is tautomerization. [2] When the isomerization occurs intramolecularly it may be called a rearrangement reaction.
Isotopes are nuclides having the same number of protons: e.g. carbon-12 and carbon-13.; Isobars are nuclides having the same mass number (i.e. sum of protons plus neutrons): e.g. carbon-12 and boron-12.
Once a substitution is made on a parent molecule, its structural symmetry is usually reduced, meaning that atoms that were formerly equivalent may no longer be so. Thus substitution of two or more equivalent atoms by the same element may generate more than one positional isomer. The classical example is the derivatives of benzene. Its six ...
Quantities, Units and Symbols in Physical Chemistry – this IUPAC "Green Book" covers many ISO 31 definitions; IEC 60027 Letter symbols to be used in electrical technology; ISO 1000 SI Units and Recommendations for the use of their multiples and of certain other units (bundled with ISO 31 as the ISO Standards Handbook – Quantities and units)
Isoelectronicity is a phenomenon observed when two or more molecules have the same structure (positions and connectivities among atoms) and the same electronic configurations, but differ by what specific elements are at certain locations in the structure.