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[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.
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 ...
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 ...
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 ...
The Lewis diagram for NCN 2-showing the symmetric carbodiimide form (1) and the asymmetric cyanamide form (2) Inorganic carbodiimides (or cyanamides depending on the NCN 2-form) design a family of compounds containing the carbodiimide (or cyanamide) anion NCN 2-bonded to an inorganic group such as a metal. This anion exhibits pseudochalcogenide ...
Two-pore channels (TPCs) are eukaryotic intracellular voltage-gated and ligand gated cation selective ion channels. [1] There are two known paralogs in the human genome, TPC1s and TPC2s. [2] In humans, TPC1s are sodium selective and TPC2s conduct sodium ions, calcium ions and possibly hydrogen ions. Plant TPC1s are non-selective channels.
The following chart shows the solubility of various ionic compounds in water at 1 atm pressure and room temperature (approx. 25 °C, 298.15 K). "Soluble" means the ionic compound doesn't precipitate, while "slightly soluble" and "insoluble" mean that a solid will precipitate; "slightly soluble" compounds like calcium sulfate may require heat to precipitate.
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.