Search results
Results From The WOW.Com Content Network
Phosphorus is a member of the pnictogens, together with nitrogen, arsenic, antimony, bismuth, and moscovium, and consequently shares properties with them. Phosphorus is an element essential to sustaining life largely through phosphates, compounds containing the phosphate ion, PO 4 3−.
Violet phosphorus (right) by a sample of red phosphorus (left) Hitorff's phosphorus structure. Monoclinic phosphorus, violet phosphorus, or Hittorf's metallic phosphorus is a crystalline form of the amorphous red phosphorus. [15] [16] In 1865, Johann Wilhelm Hittorf heated red phosphorus in a sealed tube at 530 °C. The upper part of the tube ...
Phosphorus in the form of phosphates occur in compounds important to life, such as DNA and ATP. Humans consume approximately 1 g of phosphorus per day. [25] Phosphorus is found in foods such as fish, liver, turkey, chicken, and eggs. Phosphate deficiency is a problem known as hypophosphatemia. A typical 70 kg human contains 480 g of 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.
In turn, other materials (such as nickel) can be used to quench the afterglow and shorten the decay part of the phosphor emission characteristics. Many phosphor powders are produced in low-temperature processes, such as sol-gel , and usually require post-annealing at temperatures of ~1000 °C, which is undesirable for many applications.
This type of environment is the main reason why phosphorites are commonly associated with silica and chert. Estuaries are also known as a phosphorus “trap”. This is because coastal estuaries contain a high productivity of phosphorus from marsh grass and benthic algae which allow an equilibrium exchange between living and dead organisms. [11]
The characteristic properties of elemental metals and nonmetals are quite distinct, as shown in the table below. Metalloids, straddling the metal-nonmetal border , are mostly distinct from either, but in a few properties resemble one or the other, as shown in the shading of the metalloid column below and summarized in the small table at the top ...
When it is converted to the covalent red phosphorus, the density goes to 2.2–2.4 g/cm 3 and melting point to 590 °C, and when white phosphorus is transformed into the (also covalent) black phosphorus, the density becomes 2.69–3.8 g/cm 3 and melting temperature ~200 °C. Both red and black phosphorus forms are significantly harder than ...