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The valence is the combining capacity of an atom of a given element, determined by the number of hydrogen atoms that it combines with. In methane, carbon has a valence of 4; in ammonia, nitrogen has a valence of 3; in water, oxygen has a valence of 2; and in hydrogen chloride, chlorine has a valence of 1.
Cobalt is also used in the petroleum industry as a catalyst when refining crude oil. This is to purge it of sulfur, which is very polluting when burned and causes acid rain. [11] Cobalt is the active center of a group of coenzymes called cobalamins. Vitamin B 12, the best-known example of the type, is an essential vitamin for all animals.
Cobalt(II) nitrate exists in the anhydrous form and the hydrate form, of which the hexahydrate is the most common. Cobalt nitrate hexahydrate (Co(NO 3) 2 ·6H 2 O) is a red deliquescence crystal that is easily soluble in water, [12] and its molecule contains cobalt(II) hydrated ions ([Co(H 2 O) 6] 2+) and free nitrate ions. [13]
This is a list of chemical elements and their atomic properties, ordered by atomic number (Z).. Since valence electrons are not clearly defined for the d-block and f-block elements, there not being a clear point at which further ionisation becomes unprofitable, a purely formal definition as number of electrons in the outermost shell has been used.
The valence electrons (here 3s 2 3p 3) are written explicitly for all atoms. Electron configurations of elements beyond hassium (element 108) have never been measured; predictions are used below. As an approximate rule, electron configurations are given by the Aufbau principle and the Madelung rule.
The valence shell is the set of orbitals which are energetically accessible for accepting electrons to form chemical bonds. For main-group elements, the valence shell consists of the ns and np orbitals in the outermost electron shell.
The compounds cobalt silicate and cobalt(II) aluminate (CoAl 2 O 4, cobalt blue) give a distinctive deep blue color to glass, ceramics, inks, paints and varnishes. Cobalt occurs naturally as only one stable isotope, cobalt-59. Cobalt-60 is a commercially important radioisotope, used as a radioactive tracer and for the production of high-energy ...
Cobalt(II,III) oxide is an inorganic compound with the formula Co 3 O 4. It is one of two well characterized cobalt oxides. It is a black antiferromagnetic solid. As a mixed valence compound, its formula is sometimes written as Co II Co III 2 O 4 and sometimes as CoO•Co 2 O 3. [4]