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However the group 12 metals have much lower melting and boiling points since their full d subshells prevent d–d bonding, which again tends to differentiate them from the accepted transition metals. Mercury has a melting point of −38.83 °C (−37.89 °F) and is a liquid at room temperature.
General chemical structure of a metallocene compound, where M is a metal cation. A metallocene is a compound typically consisting of two cyclopentadienyl anions (C 5 H − 5, abbreviated Cp) bound to a metal center (M) in the oxidation state II, with the resulting general formula (C 5 H 5) 2 M. Closely related to the metallocenes are the metallocene derivatives, e.g. titanocene dichloride or ...
Catalysis (/ k ə ˈ t æ l ə s ɪ s /) is the increase in rate of a chemical reaction due to an added substance known as a catalyst [1] [2] (/ ˈ k æ t əl ɪ s t /). Catalysts are not consumed by the reaction and remain unchanged after it. [ 3 ]
Periodic table of the chemical elements showing the most or more commonly named sets of elements (in periodic tables), and a traditional dividing line between metals and nonmetals. The f-block actually fits between groups 2 and 3 ; it is usually shown at the foot of the table to save horizontal space.
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 ...
Heterobimetallic catalysis is an approach to catalysis that employs two different metals to promote a chemical reaction. Included in this definition are cases ( Scheme 1 ) where: 1 ) each metal activates a different substrate ( synergistic catalysis , used interchangeably with the terms "cooperative" and "dual" catalysis.
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 ...
Ligand selection requires critical consideration in many practical areas, including bioinorganic and medicinal chemistry, homogeneous catalysis, and environmental chemistry. Ligands are classified in many ways, including: charge, size (bulk), the identity of the coordinating atom(s), and the number of electrons donated to the metal ( denticity ...