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White phosphorus is also the most common, industrially important, and easily reproducible allotrope, and for these reasons is regarded as the standard state of phosphorus. The most stable form is the black allotrope , which is a metallic looking, brittle and relatively non-reactive semiconductor (unlike the white allotrope, which has a white or ...
Phosphorus, as black phosphorus. Phosphorus in its most thermodynamically stable black form, is a lustrous and comparatively unreactive solid with a density of 2.69 g/cm 3, and is soft (MH 2.0) and has a flaky comportment. It sublimes at 620 °C. Black phosphorus has an orthorhombic crystalline structure (CN 3).
Phosphorus is a chemical element with the symbol P and the atomic number 15. Elemental phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly reactive, phosphorus is never found as a free element on Earth. It has an occurrence in the Earth's crust of about 0.1%, generally occurring as phosphate in ...
The measurement of sales of popular music starts high relative to the wedding anniversary scale, concentrating on gold and platinum (see gold album).Likewise, credit card companies usually have a "gold card" and a "platinum card" (many formerly had a "silver card" then followed by a "gold card", but due to similarity in appearance between silver and platinum these were often discontinued with ...
A metalloid is a chemical element which has a preponderance of properties in between, or that are a mixture of, those of metals and nonmetals.The word metalloid comes from the Latin metallum ("metal") and the Greek oeides ("resembling in form or appearance"). [1]
The platinum-group metals [a] (PGMs) are six noble, precious metallic elements clustered together in the periodic table. These elements are all transition metals in the d-block (groups 8, 9, and 10, periods 5 and 6). [1] The six platinum-group metals are ruthenium, rhodium, palladium, osmium, iridium, and platinum.
A generalization is that minerals with metallic or adamantine lustre tend to have higher specific gravities than those having a non-metallic to dull lustre. For example, hematite , Fe 2 O 3 , has a specific gravity of 5.26 [ 89 ] while galena , PbS, has a specific gravity of 7.2–7.6, [ 90 ] which is a result of their high iron and lead ...
Platinum is a chemical element; it has symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal. Its name originates from Spanish platina, a diminutive of plata "silver". [7] [8] Platinum is a member of the platinum group of elements and group 10 of the periodic table of ...