Phosphorus and Sulphur

The oxygen atoms in all phosphates may, in principle, be partially or wholly replaced by sulphur atoms and many such thio-phosphorus compounds are known. Analogous seleno-phosphorus compounds are also known as well as a few telluro derivatives. 

Thio-phosphorus compounds may contain sulphur either as a terminal atom P=S, or in a bridge situation P-S-X (X = P, S, C, H etc.). Both these arrangements exist in the phosphorus sulphides (Chapter 2.4). 

Most known phosphorus-sulphur compounds are of the A.W type. Physical data for these derivatives confirm that n bonding is less important in P-S bonds than it is in P-0 bonds, but it is greater in terminal P=S than in bridging P-S linkages. Relative n bond orders have been estimated (from NMR data) as 

The P=S bond is less polar but more polarisable than the P=0 bond. 

The reverse process of conversion of P=S to P=0 can sometimes be carried out with 3-chloroper-benzoic acid or dimethyl sulphoxide containing a little iodine. With some oxidising agents, however, unwanted side reactions are liable to occur [8]. 

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In each of the examples given so far each element has achieved a noble gas configuration as a result of electron sharing. There are. however, many examples of stable covalent compounds in which noble gas configurations are not achieved, or are exceeded. In the compounds of aluminium, phosphorus and sulphur, shown below, the central atoms have 6. 10 and 12 electrons respectively involved in bondinc... 

Most cast irons, except those fully decarburised during malleabilising, give coatings of the chromium carbide type. In view of the great variations in composition of cast irons, reproducibility of results can be achieved only by careful control of specification. High phosphorus and sulphur contents are detrimental to the formation of non-porous coatings. 

Inorganic phosphorus- and sulphur-containing peroxy species. . 977... 

Granat, L., Rodhe, H., and Hallberg, R. O. (1976). The global sulphur cycle. In Nitrogen, Phosphorus and Sulphur - Global Cycles" (B. H. Svensson and R. Soderlund, eds) pp. 89-134. SCOPE Report 7, Ecol. Bull., Stockholm. 

The simultaneous analysis of orthophosphate, glycerol phosphates, and inositol phosphates has been achieved by spectrophotometric analysis of the molybdovanadate complexes. Also, a sensitive and selective chemiluminescent molecular emission method for the estimation of phosphorus and sulphur is described, which is based on passing solutions into a cool, reducing, nitrogen-hydrogen diffusion flame. For organic compounds it was usually necessary to prepare test solutions by an oxygen-flask combustion technique. 

He ZL, Wu J, O Donnell AG, Syers JK (1997) Seasonal responses in microbial biomass carbon, phosphorus and sulphur in soils under pasture. Biol Fertil Soils 24 421 128... 

This is a selective detector for phosphorus and sulphur-containing compounds which makes use of the... 

Suppliers of visible spectrophotometers are reviewed in Table 1.1. Spectroscopic methods are applicable to the determination of phenols, chlorophenols, amines, mixtures of organics, boron, halogens, total nitrogen and total phosphorus in soils, cationic surfactants, carbohydrates, total nitrogen, phosphorus and sulphur in non-saline sediments, boron, total organic carbon, total sulphur and arsenic in saline sediments, cationic surfactants, adenosine triphosphate and total organic carbon in sludges. 

In clay samples Zr-Th-rich coffinite was found around remnants of zircon. It is likely that it is the result of solid solution with zircon, ZrSi04 and thorite, ThSi04, which are isostruc-tural with coffinite (Finch Murakami 1999 Jensen Ewing 2001). The presence of phosphorus and sulphur in coffinite suggests that both elements substituted for Si in the coffinite structure. A previous study at the Bangombe site in Gabon has clearly shown that coffinites are most important secondary minerals for the retention of fissiogenic lanthanides and actinides (Stille et al. 2003). 

For vanadium and chromium the first ionization energies are much lower than the first ionization energies of phosphorus and sulphur, respectively. This explains the high heats of formation of VC13 and CrCl3. In uranium, the tetravalent state is more stable than that in tungsten because uranium as an actinide has a different electron configuration. 

Phosphorus and sulphur are only sparingly soluble in the liquid, but sulphur monochloride is miscible.10 The binary systems formed by liquid sulphur dioxide with the tetrachlorides of carbon, tin and titanium, and with the tetrabromide of tin, have been investigated. The liquids are only partly miscible at lower temperatures and compound... 

Volume 10 is devoted to formation and solvolysis of esters and related reactions, with discussion of the effect of neighbouring groups and biological implications, e.g. enzyme action, where appropriate. The first chapter deals mainly with esters of the inorganic acids of phosphorus and sulphur, Chapter 2 with the formation and solvolysis of esters of organic acids and the final chapter with the solvolysis of related derivatives of carboxylic acids, e.g. halides, amides, anhydrides, cyanides, carbamic acid derivatives. 

With more water, it passes into solution dilute solutions, which are brownish-yellow or red, according to the concentration, evolve chlorine and become blue on standing, undergoing reduction to the tetravalent state. On evaporation to dryness, aU the chlorine is evolved and the residue consists of the. pentoxide. Vanadium oxytrichloride is also soluble in ether and alcohol. It dissolves chlorine, bromine, iodine, yellow phosphorus, and sulphur, and is miscible with various liquid hydrocarbons and chlorinated hydrocarbons its use as an industrial solvent has therefore been suggested. ... 

Arsenic, when gently heated in the presence of air or oxygen, exhibits phosphorescence 7 which, as with phosphorus and sulphur, is accompanied by oxidation, arsenious oxide containing about 3 per cent, of arsenic oxide being produced. No ozone is formed, nor is there ionisation, as in the phosphorescence of the two elements mentioned. The arsenic oxide appears to be a primary product formed directly from the arsenic, as the lower oxide does not yield it under such conditions. Arsenious oxide is formed slowly below 200° C. without luminescence, but between 250° and 310° C. the glow appears suddenly 8 so long as the pressure is between certain limits,9 outside of which no luminescence is observed. The lower limit, 4 to 10 mm. Hg, falls with increasing temperature, while the upper limit, 200 to 700 mm. Hg, rises... 

Phosphorus Trisulphide (P2S3).—The calculated quantities of dry amorphous phosphorus and sulphur are carefully melted together in a fireclay crucible. The product is then cooled and broken up. 

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