Phosphorus forms

Phosphorus forms a number of oxides, the best established being phosphorus(lll) oxide, P40f, and phosphorus(V) oxide, P40,o-The + 5 oxide is the more stable and the + 3 oxide is easily oxidised. 

Phosphorus forms a large number of oxoacids, many of which cannot be isolated but do form stable salts. In general, ionisable hydrogen is bonded to the phosphorus through an oxygen atom hydrogen atoms attached directly to phosphorus are not ionisable. 

Phosphorus exists as white and red phosphorus. The former allotrope may be preserved in the dark at low temperatures but otherwise reverts to the more stable red form. The white form is a waxy, translucent, crystalline, highly-toxic solid subliming at room temperature and inflaming in air at 35°C, so it is handled under water. The red form is a reddish violet crystalline solid which vaporizes if heated at atmospheric pressure and condenses to give white phosphorus. The red form ignites in air at 260°C. Both are insoluble in water, and white phosphorus can be stored beneath it. Phosphorus forms a host of compounds such as phosphine, tri- and penta-halides, tri-, tetra- and penta-oxides, oxyacids including hypophosphorous, orthophosphorous and orthophosphoric acids. 

The element phosphorus forms a variety of allotropic forms in the solid state. In the chemistry stockroom, you are likely to find red phosphorus and possibly white phosphorus (Figure B). As you can see, white phosphorus has the molecular formula P4, whereas red phosphorus might be represented as Px, where x is a very large number. The difference in properties between the two allotropes reflects the difference in their bonding patterns, molecular versus network covalent ... 

Phosphorus forms a wide variety of oxoanions, which outnumber those formed by any other element except silicon [ 1 ]. Many of these anionic hgands are of industrial importance and their derivatives are essential components of numerous biological processes. Some of the more common examples include orthophosphate PO " (1), phosphite HPO " (2) and metaphosphate PO3 (3). 

C09-0138. In the following reactions, phosphorus forms a bond to a Row 2 element. In one reaction, phosphoms donates two electrons to make the fourth bond, but in the other reaction, phosphorus accepts two electrons to make the fourth bond. Use Lewis structures of starting materials and products to determine in which reaction phosphoms is a donor and in which it acts as an acceptor. 

C14-0138. Phosphorus forms white crystals made up of P4 molecules. There are two forms of white crystalline phosphorus, called a and p. The difference between P4 a and P4 is determined by the way the P4 molecules pack together In the crystal lattice. The a form is always obtained when liquid phosphoras freezes. However, at temperatures below - 77 ° C, the P4 cj crystals change spontaneously to P4 ... 

Lanthanum is a naturally occurring trivalent rare earth element (atomic number 57). Lanthanum carbonate quickly dissociates in the acidic environment of the stomach, where the lanthanum ion binds to dietary phosphorus, forming an insoluble compound that is excreted in the feces. Lanthanum has been shown to remove more than 97% of dietary phosphorus... 

Phosphorus vapor consists of tetrahedral P4 molecules, and at higher temperatures also of P2 molecules (P=Pbond length 190 pm). White phosphorus forms by condensation of the vapor it also consists of P4 molecules. Liquid phosphorus normally consists of P4 molecules, but at a pressure of 1 GPa and 100 °C polymeric liquid phosphorus is formed which is not miscible with liquid P4. 

The only element that was discovered in body fluids (urine). This is plausible, as P plays a main role in all life processes. It is one of the five elements that make up DNA (besides C, H, N, and 0 evolution did not require anything else to code all life). The P-O-P bond, phosphoric acid anhydride, is the universal energy currency in cells. The skeletons of mammals consists of Ca phosphate (hydroxylapatite). The element is encountered in several allotropic modifications white phosphorus (soft, pyrophoric P4, very toxic), red phosphorus (nontoxic, used to make the striking surface of matchboxes), black phosphorus (formed under high pressures). Phosphates are indispensable as fertilizer, but less desirable in washing agents as the waste water is too concentrated with this substance (eutrophication). It has a rich chemistry, is the basis for powerful insecticides, but also for warfare agents. A versatile element. 

Phosphorus forms two covalent compounds with chlorine, PCI, and PCI,. Discuss these compounds in terms of the octet rule. 

Although the subject of stability of complexes will be discussed in greater detail in Chapter 19 it is appropriate to note here some of the general characteristics of the metal-ligand bond. One of the most relevant principles in this consideration is the hard-soft interaction principle. Metal-ligand bonds are acid-base interactions in the Lewis sense, so the principles discussed in Sections 9.6 and 9.8 apply to these interactions. Soft electron donors in which the donor atom is sulfur or phosphorus form more stable complexes with soft metal ions such as Pt2+ or Ag+, or with metal atoms. Hard electron donors such as H20, NH3( or F generally form stable complexes with hard metal ions like Cr3+ or Co3+. 

The irritant effects of phosphorus trichloride result primarily from the action of the strong acids (hydrochloric acid and acids of phosphorus) formed on contact with water. ... 

A.J.G. Blesa, M.A. (1988) The dissolution of magnetite by nitrilotriacetatoferrate(II). J. Chem. Soc. Earaday Trans. I. 84 9-18 Delgado, A. Torrent, J. (2000) Phosphorus forms and desorption patterns in heavily fertilized calcareous and limed acid soils. Soil Sci. Soc. Am. J. 64 2031-2037 Delgado, A.V. Gonzalez-Caballero, F. (1998) Inorganic particles as colloidal models. Effects of size and shape on the electrokinetics of hematite (a-Fe203). Croatica Chemica Acta 71 1087-1104... 

Turner, B.L. and Haygarth, P.M. (2000) Phosphorus forms and concentrations in leachate under four grassland soil types. Soil Science Society of America Journal 64(3), 1090-1099. 

Oxygen difluoride reacts with nonmetals, such as sulfur and phosphorus, forming fluorides and oxyfluorides ... 

Phosphorus forms three compounds with hydrogen, which cannot be obtained by the direct combination of their elements. 

Unlike carbon, which forms only stable tetravalent compounds, phosphorus forms stable trivalent, tetravalent, and pentavalent compounds. A phosphoryl transfer reaction such as... 

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