When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Chemical compound - Wikipedia

    en.wikipedia.org/wiki/Chemical_compound

    [16] [17] [18] A molecule may be homonuclear, that is, it consists of atoms of one chemical element, as with two atoms in the oxygen molecule (O 2); or it may be heteronuclear, a chemical compound composed of more than one element, as with water (two hydrogen atoms and one oxygen atom; H 2 O). A molecule is the smallest unit of a substance that ...

  3. Formal charge - Wikipedia

    en.wikipedia.org/wiki/Formal_charge

    Formal charges in ozone and the nitrate anion. In chemistry, a formal charge (F.C. or q*), in the covalent view of chemical bonding, is the hypothetical charge assigned to an atom in a molecule, assuming that electrons in all chemical bonds are shared equally between atoms, regardless of relative electronegativity.

  4. UNIFAC - Wikipedia

    en.wikipedia.org/wiki/UNIFAC

    where and are the molar weighted segment and area fractional components for the -th molecule in the total system and are defined by the following equation; is a compound parameter of , and . z {\displaystyle z} is the coordination number of the system, but the model is found to be relatively insensitive to its value and is frequently quoted as ...

  5. Chemical formula - Wikipedia

    en.wikipedia.org/wiki/Chemical_formula

    An example of the difference is the empirical formula for glucose, which is CH 2 O (ratio 1:2:1), while its molecular formula is C 6 H 12 O 6 (number of atoms 6:12:6). For water, both formulae are H 2 O. A molecular formula provides more information about a molecule than its empirical formula, but is more difficult to establish.

  6. Dissociation (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Dissociation_(chemistry)

    Dissociation in chemistry is a general process in which molecules (or ionic compounds such as salts, or complexes) separate or split into other things such as atoms, ions, or radicals, usually in a reversible manner.

  7. Stoichiometry - Wikipedia

    en.wikipedia.org/wiki/Stoichiometry

    If a reaction network has n reactions and m participating molecular species, then the stoichiometry matrix will have correspondingly m rows and n columns. For example, consider the system of reactions shown below: S 1 → S 2 5 S 3 + S 2 → 4 S 3 + 2 S 2 S 3 → S 4 S 4 → S 5. This system comprises four reactions and five different molecular ...

  8. Structural formula - Wikipedia

    en.wikipedia.org/wiki/Structural_formula

    Skeletal structural formula of Vitamin B 12.Many organic molecules are too complicated to be specified by a molecular formula.. The structural formula of a chemical compound is a graphic representation of the molecular structure (determined by structural chemistry methods), showing how the atoms are connected to one another. [1]

  9. Lewis structure - Wikipedia

    en.wikipedia.org/wiki/Lewis_structure

    [1] [2] [3] Introduced by Gilbert N. Lewis in his 1916 article The Atom and the Molecule, a Lewis structure can be drawn for any covalently bonded molecule, as well as coordination compounds. [4] Lewis structures extend the concept of the electron dot diagram by adding lines between atoms to represent shared pairs in a chemical bond.