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Zinc. hexagonal close-packed (hcp) ( hP2) 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.
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.
Cadmium. hexagonal close-packed (hcp) ( hP2) Cadmium is a chemical element; it has symbol Cd and atomic number 48. This soft, silvery-white metal is chemically similar to the two other stable metals in group 12, zinc and mercury. Like zinc, it demonstrates oxidation state +2 in most of its compounds, and like mercury, it has a lower melting ...
Zinc acetate is a salt with the formula Zn (CH 3 CO 2) 2, which commonly occurs as the dihydrate Zn (CH 3 CO 2) 2 ·2H 2 O. Both the hydrate and the anhydrous forms are colorless solids that are used as dietary supplements. When used as a food additive, it has the E number E650.
The atomic mass ( ma or m) is the mass of an atom. Although the SI unit of mass is the kilogram (symbol: kg), atomic mass is often expressed in the non-SI unit dalton (symbol: Da) – equivalently, unified atomic mass unit (u). 1 Da is defined as 1⁄12 of the mass of a free carbon-12 atom at rest in its ground state. [ 1]
Atomic number is the number of protons, and therefore also the total positive charge, in the atomic nucleus. The Rutherford–Bohr model of the hydrogen atom ( Z = 1) or a hydrogen-like ion ( Z > 1 ). In this model, it is an essential feature that the photon energy (or frequency) of the electromagnetic radiation emitted (shown) when an electron ...
Zinc sulfide (or zinc sulphide) is an inorganic compound with the chemical formula of ZnS. This is the main form of zinc found in nature, where it mainly occurs as the mineral sphalerite . Although this mineral is usually black because of various impurities, the pure material is white, and it is widely used as a pigment.
Relative atomic mass (symbol: Ar; sometimes abbreviated RAM or r.a.m. ), also known by the deprecated synonym atomic weight, is a dimensionless physical quantity defined as the ratio of the average mass of atoms of a chemical element in a given sample to the atomic mass constant. The atomic mass constant (symbol: mu) is defined as being 1 ...