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  2. Lewis structure - Wikipedia

    en.wikipedia.org/wiki/Lewis_structure

    In terms of Lewis structures, formal charge is used in the description, comparison, and assessment of likely topological and resonance structures [7] by determining the apparent electronic charge of each atom within, based upon its electron dot structure, assuming exclusive covalency or non-polar bonding.

  3. Calcium nitride - Wikipedia

    en.wikipedia.org/wiki/Calcium_nitride

    α-Calcium nitride adopts an anti-bixbyite structure, similar to Mn 2 O 3, except that the positions of the ions are reversed: calcium (Ca 2+) take the oxide (O 2−) positions and nitride ions (N 3−) the manganese (Mn 3+). In this structure, Ca 2+ occupies tetrahedral sites, and the nitride centres occupy two different types of octahedral ...

  4. Charge number - Wikipedia

    en.wikipedia.org/wiki/Charge_number

    A charge number also can help when drawing Lewis dot structures. For example, if the structure is an ion, the charge will be included outside of the Lewis dot structure. Since there is a negative charge on the outside of the Lewis dot structure, one electron needs to be added to the structure.

  5. Electron pair - Wikipedia

    en.wikipedia.org/wiki/Electron_pair

    In chemistry, an electron pair or Lewis pair consists of two electrons that occupy the same molecular orbital but have opposite spins. Gilbert N. Lewis introduced the concepts of both the electron pair and the covalent bond in a landmark paper he published in 1916.

  6. Calcium fluoride - Wikipedia

    en.wikipedia.org/wiki/Calcium_fluoride

    Calcium fluoride is the inorganic compound of the elements calcium and fluorine with the formula CaF 2. It is a white solid that is practically insoluble in water. It occurs as the mineral fluorite (also called fluorspar), which is often deeply coloured owing to impurities.

  7. Calcium phosphide - Wikipedia

    en.wikipedia.org/wiki/Calcium_phosphide

    Calcium phosphide (CP) is the inorganic compound with the formula Ca 3 P 2. It is one of several phosphides of calcium, being described as the salt-like material composed of Ca 2+ and P 3−. Other, more exotic calcium phosphides have the formula CaP / Ca 2 P 2, CaP 3, and Ca 5 P 8. Ca 3 P 2 has the appearance of red-brown crystalline powder or ...

  8. Lewis acids and bases - Wikipedia

    en.wikipedia.org/wiki/Lewis_acids_and_bases

    For example, in the formation of an ammonium ion from ammonia and hydrogen the ammonia molecule donates a pair of electrons to the proton; [11] the identity of the electrons is lost in the ammonium ion that is formed. Nevertheless, Lewis suggested that an electron-pair donor be classified as a base and an electron-pair acceptor be classified as ...

  9. Calcium - Wikipedia

    en.wikipedia.org/wiki/Calcium

    Calcium is readily complexed by oxygen chelates such as EDTA and polyphosphates, which are useful in analytic chemistry and removing calcium ions from hard water. In the absence of steric hindrance , smaller group 2 cations tend to form stronger complexes, but when large polydentate macrocycles are involved the trend is reversed.