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Zinc fingers help read DNA sequences.. Zinc is an essential trace element for humans [1] [2] [3] and other animals, [4] for plants [5] and for microorganisms. [6] Zinc is required for the function of over 300 enzymes and 1000 transcription factors, [3] and is stored and transferred in metallothioneins.
The bonding in carbon dioxide (CO 2): all atoms are surrounded by 8 electrons, fulfilling the octet rule.. The octet rule is a chemical rule of thumb that reflects the theory that main-group elements tend to bond in such a way that each atom has eight electrons in its valence shell, giving it the same electronic configuration as a noble gas.
The point group symmetry involved is of type C 4v. The geometry is common for certain main group compounds that have a stereochemically-active lone pair, as described by VSEPR theory. Certain compounds crystallize in both the trigonal bipyramidal and the square pyramidal structures, notably [Ni(CN) 5] 3−. [1]
In chemistry, the dodecahedral molecular geometry describes the shape of compounds where eight atoms or groups of atoms or ligands are arranged around a central atom defining the vertices of a snub disphenoid (also known as a trigonal dodecahedron).
[2] [3] [page needed] Pentagonal bipyramids are claimed to be promising coordination geometries for lanthanide -based single-molecule magnets , since they present no extradiagonal crystal field terms, therefore minimising spin mixing, and all of their diagonal terms are in first approximation protected from low-energy vibrations, minimising ...
It thus tends to form a covalent bond with another S − center to form S 2− 2 group, similar to elemental chlorine existing as the diatomic Cl 2. Oxygen may also behave similarly, e.g. in peroxides such as H 2 O 2. Examples: Hydrogen disulfide (S 2 H 2), the simplest inorganic disulfide; Disulfur dichloride (S 2 Cl 2), a distillable liquid.
2. One-electron bonds often have about half the bond energy of a 2-electron bond, and are therefore called "half bonds". However, there are exceptions: in the case of dilithium, the bond is actually stronger for the 1-electron Li + 2 than for the 2-electron Li 2. This exception can be explained in terms of hybridization and inner-shell effects ...
Molecular binding is an attractive interaction between two molecules that results in a stable association in which the molecules are in close proximity to each other. It is formed when atoms or molecules bind together by sharing of electrons.