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Octet rule — The bonding in carbon dioxide (CO2): all atoms are surrounded by 8 electrons, fulfilling the octet rule. The octet rule is a chemical rule of thumb that states that atoms of low (<20) atomic number tend to combine in such a way that they each… … Wikipedia
octet rule — when atoms combine to form molecules, they tend to share or transfer electrons until eight (four pairs) are in the valence shell of each atom … Medical dictionary
Octet — may refer to: Music Octet (music), ensemble consisting of eight instruments or voices, or composition written for such an ensemble Octet (Beethoven), 1793 composition by Ludwig van Beethoven Octet (Mendelssohn), 1825 composition by Felix… … Wikipedia
octet — /ok tet /, n. 1. a company of eight singers or musicians. 2. a musical composition for eight voices or instruments. 3. Pros. octave (def. 4). 4. any group of eight. Also, octette. [1860 65; OCT + et, as in duet] * * * ▪ chemistry … Universalium
18-Electron rule — The 18 electron rule is a rule of thumb used primarily in transition metal chemistry for characterizing and predicting the stability of metal complexes. Valence shells of a transition metal can accommodate 18 electrons: 2 in each of the five d… … Wikipedia
Abegg's rule — In chemistry, Abegg’s rule states that the difference between the maximum positive and negative valence of an element is frequently eight. In general, for a given chemical element (as sulfur) Abegg’s rule states that the sum of the absolute value … Wikipedia
chemical bonding — ▪ chemistry Introduction any of the interactions that account for the association of atoms into molecules, ions, crystals, and other stable species that make up the familiar substances of the everyday world. When atoms approach one another … Universalium
Hypervalent molecule — A hypervalent molecule is a molecule that contains one or more main group elements formally bearing more than eight electrons in their valence shells. Phosphorus pentachloride (PCl5), sulfur hexafluoride (SF6), the phosphate (PO43−) ion, chlorine … Wikipedia
Lewis structure — The Lewis structure of water. Lewis structures (also known as Lewis dot diagrams, electron dot diagrams, and electron dot structures) are diagrams that show the bonding between atoms of a molecule and the lone pairs of electrons that may exist in … Wikipedia
Electron counting — is a formalism used for classifying compounds and for explaining or predicting electronic structure and bonding. Many rules in chemistry rely on electron counting:*Octet rule for main group elements, especially the lighter ones such as carbon,… … Wikipedia
