Wikipedia Portalsclose
Wikipedia categoriesclose

Results 1 - 10 of 473 for  Wikipedia / Chemical substance / Wikipedia    (3565152 articles)

Chemical substance print that page


In chemistry , a chemical substance is a form of matter that has constant chemical composition and characteristic properties. [ 1 ] It cannot be separated into components by physical separation methods, i.e. without breaking chemical bonds. They can be solids, liquids or gases. Chemical

Chemical reaction print that page


elementary particles (such as illustrated by Feynman diagrams ), as well as nuclear reactions . The substance (or substances) initially involved in a chemical reaction are called reactants or reagents . Chemical reactions are usually characterized by a chemical change , and they yield one

Chemical database print that page

A chemical database is a database specifically designed to store chemical information . This information is about chemical and crystal structures, spectra, reactions and syntheses, and thermophysical data. Contents 1 Types of chemical databases 1.1 Chemical structures 1.2 Literature | 2011/9/26 23:17:19

Chemical change print that page

change.chemical changes are permanent. A chemical change changes the identity or properties of a substance and cannot be reversible. [ edit ] References ^ Carpi, Anthony, Ph.D. “Chemical Reactions.” Vision Learning. Vision Learning Inc. , 2009. Web. 6 Oct. 2009. v · d | 2011/10/5 11:23:51

Chemical nomenclature print that page

ambiguity as to what chemical compound the name refers: each chemical name should refer to a single substance . A less important aim is to ensure that each substance has a single name, although the number of acceptable names is limited. Preferably, the name also conveys some information about | 2011/9/25 17:30:47

Chemical potential print that page

definition, any chemical element or combination of elements in given proportions may be considered a substance , whether capable or not of existing by itself as a homogeneous body. Chemical potential is also referred to as partial molar Gibbs energy (see also partial molar property ). Chemical | 2011/9/25 19:00:53

Chemical element print that page


A chemical element is a pure chemical substance consisting of one type of atom distinguished by its atomic number , which is the number of protons in its nucleus . [ 1 ] Familiar examples of elements include gold , iron , copper , carbon , silicon , mercury , sodium , calcium , hydrogen

Chemistry print that page


3 Etymology 4 Definitions 5 Basic concepts 5.1 Atom 5.2 Element 5.3 Compound 5.4 Substance 5.5 Molecule 5.6 Mole and amount of substance 5.7 Ions and salts 5.8 Acidity and basicity 5.9 Phase 5.10 Redox 5.11 Bonding 5.12 Reaction 5.13 Equilibrium 5.14 Energy

Amount of substance print that page

Amount of substance appears in thermodynamic relations such as the ideal gas law , and in stoichiometric relations between reacting molecules as in the law of multiple proportions . The only other unit of amount of substance in current use is the pound mole with the symbol lb-mol, which | 2011/9/7 18:36:50

Chemical energy print that page

be the result of chemical bonds within a molecule or otherwise. Chemical energy of a chemical substance can be transformed to other forms of energy by a chemical reaction . As an example, when a fuel is burned the chemical energy is converted to heat, same is the case with digestion of food | 2011/9/20 22:40:21