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Zinc is a chemical element with the symbol Zn and atomic number 30. It is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodic table .
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.
Naturally occurring zinc (30 Zn) is composed of the 5 stable isotopes 64 Zn, 66 Zn, 67 Zn, 68 Zn, and 70 Zn with 64 Zn being the most abundant (48.6% natural abundance).Twenty-eight radioisotopes have been characterised with the most stable being 65 Zn with a half-life of 244.26 days, and then 72 Zn with a half-life of 46.5 hours.
For other isotopes, the isotopic mass is usually within 0.1 u of the mass number. For example, 35 Cl (17 protons and 18 neutrons) has a mass number of 35 and an isotopic mass of 34.96885. [7] The difference of the actual isotopic mass minus the mass number of an atom is known as the mass excess, [8] which for 35 Cl is –0.03115.
118 chemical elements have been identified and named officially by IUPAC.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).
Although mercury is an extremely rare element in the Earth's crust, [68] because it does not blend geochemically with those elements that constitute the majority of the crustal mass, mercury ores can be highly concentrated considering the element's abundance in ordinary rock. The richest mercury ores contain up to 2.5% mercury by mass, and even ...
Zinc acetate is a component of some medicines, e.g., lozenges for treating the common cold. [1] Zinc acetate can also be used as a dietary supplement. [2] As an oral daily supplement it is used to inhibit the body's absorption of copper as part of the treatment for Wilson's disease. [3]
2 Zn(NO 3) 2 → 2 ZnO + 4 NO 2 + 1 O 2. Aqueous zinc nitrate contains aquo complexes [Zn(H 2 O) 6] 2+ and [Zn(H 2 O) 4] 2+. [3] and, thus, this reaction may be better written as the reaction of the aquated ion with hydroxide through donation of a proton, as follows.