enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Terminal and nonterminal symbols - Wikipedia

    en.wikipedia.org/wiki/Terminal_and_nonterminal...

    Terminal symbols are symbols that may appear in the outputs of the production rules of a formal grammar and which cannot be changed using the rules of the grammar. Applying the rules recursively to a source string of symbols will usually terminate in a final output string consisting only of terminal symbols. Consider a grammar defined by two rules.

  3. Term symbol - Wikipedia

    en.wikipedia.org/wiki/Term_symbol

    In atomic physics, a term symbol is an abbreviated description of the total spin and orbital angular momentum quantum numbers of the electrons in a multi-electron atom. So while the word symbol suggests otherwise, it represents an actual value of a physical quantity .

  4. Terminal alkene - Wikipedia

    en.wikipedia.org/wiki/Terminal_alkene

    In organic chemistry, terminal alkenes (alpha-olefins, α-olefins, or 1-alkenes) are a family of organic compounds which are alkenes (also known as olefins) with a chemical formula C x H 2x, distinguished by having a double bond at the primary, alpha (α), or 1-position. [1]

  5. Chemical symbol - Wikipedia

    en.wikipedia.org/wiki/Chemical_symbol

    Chemical symbols are the abbreviations used in chemistry, mainly for chemical elements; but also for functional groups, chemical compounds, and other entities. Element symbols for chemical elements, also known as atomic symbols , normally consist of one or two letters from the Latin alphabet and are written with the first letter capitalised.

  6. Glossary of chemistry terms - Wikipedia

    en.wikipedia.org/wiki/Glossary_of_chemistry_terms

    Also acid ionization constant or acidity constant. A quantitative measure of the strength of an acid in solution expressed as an equilibrium constant for a chemical dissociation reaction in the context of acid-base reactions. It is often given as its base-10 cologarithm, p K a. acid–base extraction A chemical reaction in which chemical species are separated from other acids and bases. acid ...

  7. Electron acceptor - Wikipedia

    en.wikipedia.org/wiki/Electron_acceptor

    Paraquat, the dication on the left, functions as an electron acceptor, disrupting respiration in plants. In biology, a terminal electron acceptor often refers to either the last compound to receive an electron in an electron transport chain, such as oxygen during cellular respiration, or the last cofactor to receive an electron within the electron transfer domain of a reaction center during ...

  8. List of chemical elements - Wikipedia

    en.wikipedia.org/wiki/List_of_chemical_elements

    A chemical element, often simply called an element, is a type of atom which has a specific number of protons in its atomic nucleus (i.e., a specific atomic number, or Z). [ 1 ] The definitive visualisation of all 118 elements is the periodic table of the elements , whose history along the principles of the periodic law was one of the founding ...

  9. Periodic table - Wikipedia

    en.wikipedia.org/wiki/Periodic_table

    The chemical elements are what the periodic table classifies and organizes. Hydrogen is the element with atomic number 1; helium, atomic number 2; lithium, atomic number 3; and so on. Each of these names can be further abbreviated by a one- or two-letter chemical symbol; those for hydrogen, helium, and lithium are respectively H, He, and Li. [6]