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White phosphorus, yellow phosphorus or simply tetraphosphorus (P 4) exists as molecules of four phosphorus atoms in a tetrahedral structure, joined by six phosphorus—phosphorus single bonds. [1] The free P 4 molecule in the gas phase has a P-P bond length of r g = 2.1994(3) Å as was determined by gas electron diffraction . [ 2 ]
Under standard conditions, red phosphorus is more stable than white phosphorus, but less stable than the thermodynamically stable black phosphorus. The standard enthalpy of formation of red phosphorus is −17.6 kJ/mol. [3] Red phosphorus is kinetically most stable. Being polymeric, red phosphorus is insoluble in solvents. It shows ...
Red phosphorus may be formed by heating white phosphorus to 250 °C (523 K) or by exposing white phosphorus to sunlight. [13] Phosphorus after this treatment is amorphous, before crystallising upon further heating. In this sense, red phosphorus is technically not an allotrope, but rather an intermediate phase between white and violet phosphorus ...
White phosphorus, yellow phosphorus, or simply tetraphosphorus (P 4) is an allotrope of phosphorus. It is a translucent waxy solid that quickly yellows in light (due to its photochemical conversion into red phosphorus ), [ 2 ] and impure white phosphorus is for this reason called yellow phosphorus.
A protein structure database is a database that is modeled around the various experimentally determined protein structures. The aim of most protein structure databases is to organize and annotate the protein structures, providing the biological community access to the experimental data in a useful way.
People exposed to white phosphorus can suffer severe and sometimes deadly bone-deep burns. It can cause organs to shut down, and burns on just 10% of the body can be fatal, HRW said.
A representation of the 3D structure of the protein myoglobin showing turquoise α-helices. This protein was the first to have its structure solved by X-ray crystallography. Toward the right-center among the coils, a prosthetic group called a heme group (shown in gray) with a bound oxygen molecule (red).
It’s also lower in calories (408 to be exact) and carbohydrates (86 grams), but higher in protein (16 grams) and fiber (13 grams, which is more than 3.5 times the amount of fiber in white flour).