Phosphorus, nitric acid

Compounds of Gold and Phosphorus.—Phosphine reacts with a solution of auric chloride in anhydrous ether, forming auric phosphide, AuP, a substance decomposed by water or potassium-hydroxide solution, with formation of phosphine and phosphoric add.2 At 100° to 110° C. it-undergoes oxidation in the air. Heating in a current of carbon dioxide causes volatilization of phosphorus. Nitric acid oxidizes the phosphorus, leaving a residue of metallic gold. These reactions indicate the substance to be an alloy of gold and phosphorus. 

Both white and red phosphorus dissolve in, for example, concentrated nitric acid to form phosphoricfV) acid, the reaction between hot acid and white phosphorus being particularly violent. 

Dinitrogeri pentoxide is the anhydride of nitric acid and is prepared by removing water from pure nitric acid by means of phosphorus (V) oxide. It is a crystalline solid having the ionic structure of (N02) (N03) , nitronium nitrate (the nitronium ion is mentioned later). It decomposes above 273 K, thus ... 

Phosphorus(V) oxide will remove water from acids to give the acid anhydride. For example, if nitric acid is distilled with it. dinitrogen pentoxide is formed ... 

Unlike phosphorus pentoxide, this oxide cannot be made directly. Arsenic(V) acid, H3ASO4 (strictly, tetraoxoarsenic acid), is first prepared by oxidising arsenic(III) oxide with concentrated nitric acid or some other strong oxidising agent ... 

Tetraoxophosphoric acid, H3PO4 — This is prepared in the laboratory either by dissolving phosphorus(V) oxide in water (giving trioxophosphoric acid) and then heating to give the tetraoxo-acid or by heating violet phosphorus with 33% nitric acid, which oxidises it thus ... 

Phosphorus. The presence of phosphorus may be indicated by a smell of phosphine during the sodium fusion. Treat 1 ml. of the fusion solution with 3 ml. of eoneentrated nitric acid and boil for one minute. Cool and add an equal volume of ammonium molybdate reagent. Warm the mixture to 40-50°, and allow to stand. If phosphorus is present, a yellow erystalline precipitate of ammonium phosphomolybdate wUl separate. 

Phosphorus trichloride Acetic acid, aluminum, chromyl dichloride, dimethylsulfoxide, hydroxylamine, lead dioxide, nitric acid, nitrous acid, organic matter, potassium, sodium water... 

Polycyclic aromatic hydrocarbons (PAH) Apply sample solution and dry. Place TLX2 plate for 20 min in a twin-trough chamber containing phosphorus pentoxide to which 2 to 3 ml cone, nitric acid have been added. PAH nitrated by nitrous fumes. [20]... 

When distilled with phosphorus pentoxide, camphor yields cymene, and with iodine, carvacrol. Both of these bodies are para-derivatives of benzene. On oxidation with nitric acid camphor yields many acids, of which the chief are camphoric acid, CjgHjgO, camphanic acid, CjoHj O, and camphoronic acid, CgHj Og. The constitution of these acids has an important bearing on that of camphor. Many formulae have been suggested for camphor during the past few years, but that of Bredt is now universally accepted, and has received complete confirmation by Komppa s synthesis of camphoric acid. This synthesis confirms the formula for camphoric acid as—... 

Acetoxypropyl)-2-methylimidazole (182 g) is gradually dissolved In fuming nitric acid (d = 1. 52 26 cc) with stirring, the temperature being kept at about 2°C. Phosphorus pent-oxide (20 g) is added, with caution, to the resulting solution and while maintaining the temperature at about 2°C. Afterwards, the reaction mixture is stirred for a further 3 hours 30 minutes at 2°C and poured onto ice (180 g). 

Nitric acid works Paraffin oil (kerosene) works Petrochemical works Petroleum works Phosphorus works Picric acid works Producer gas works Pyridine works Selenium works Smelting works Sulfate of ammonia works and chloride of ammonia works... 

Resistance to corrosion Most authors who compare resistance to corrosion of electroless nickel with that of electrodeposited nickel conclude that the electroless deposit is the superior material when assessed by salt spray testing, seaside exposure or subjection to nitric acid. Also, resistance to corrosion of electroless nickel is said to increase with increasing phosphorus level. However, unpublished results from International Nickel s Birmingham research laboratory showed that electroless nickel-phosphorus and electrolytic nickel deposits were not significantly different on roof exposure or when compared by polarisation data. 

Phosphorus from organophosphorus compounds, which are combusted to give mainly orthophosphate, can be absorbed by either sulphuric acid or nitric acid and readily determined spectrophotometrically either by the molybdenum blue method or as the phosphovanadomolybdate (Section 17.39). 

The method can be applied to the determination of phosphorus in a wide variety of materials, e.g. phosphate rock, phosphatic fertilisers and metals, and is suitable for use in conjunction with the oxygen-flask procedure (Section 3.31). In all cases it is essential to ensure that the material is so treated that the phosphorus is converted to orthophosphate this may usually be done by dissolution in an oxidising medium such as concentrated nitric acid or in 60 per cent perchloric acid. 

Prepd by dehydrating coned nitric acid with phosphorus pentoxide (Refs 3 4). Explds if heated suddenly (Ref 4). Can also be prepd by the flash photolysis of 02-N20-He mixts (Ref 11), and by the radiolysis of N2O4—HN03 with 7 rays (Ref 1.2)... 

The analysis of phosphates and phosphonates is a considerably complex task due to the great variety of possible molecular structures. Phosphorus-containing anionics are nearly always available as mixtures dependent on the kind of synthesis carried out. For analytical separation the total amount of phosphorus in the molecule has to be ascertained. Thus, the organic and inorganic phosphorus is transformed to orthophosphoric acid by oxidation. The fusion of the substance is performed by the addition of 2 ml of concentrated sulfuric acid to — 100 mg of the substance. The black residue is then oxidized by a mixture of nitric acid and perchloric acid. The resulting orthophosphate can be determined at 8000 K by atom emission spectroscopy. The thermally excited phosphorus atoms emit a characteristic line at a wavelength of 178.23 nm. The extensity of the radiation is used for quantitative determination of the phosphorus content. 

C. By Oxidation.—This year s literature has been notable for attempts to study the details of certain phosphine oxidation reactions. In one such investigation nitric acid was found to oxidize phosphines, or phosphine sulphides, to phosphine oxides with inversion of configuration at phosphorus, whereas dinitrogen tetroxide, in the absence of acid, was found to oxidize the same compounds with predominant retention. The partial racemization observed with the latter reagent was probably due to the racemization of the oxides, since methylphenyl-n-propylphosphine oxide... 

An air/nitric acid/phosphorus mixture in the gaseous state combusts spontaneously. The same is true for hot phosphorus or in the molten state when nitrogen oxides are present. 

Phosphorus trichloride detonates in contact with nitric acid. The same may occur during the highly exothermic interaction between this chloride and sodium peroxide. 

It is usually preferable to oxidise the compound directly as follows. Intimately mix 0 02-0-05 g. of the compound with 3 g. of sodium peroxide and 2 g. of anhydrous sodium carbonate in a nickel crucible. Heat the crucible and its contents with a small flame, gently at first, afterwards more strongly until the contents are fused, and continue heating for a further 10 minutes. Allow to stand, extract the contents of the crucible with water, and filter. Add excess of concentrated nitric acid to the filtrate and test with ammonium molybdate reagent as above. A yellow precipitate indicates the presence of phosphorus. It must be borne in mind that the above treatment will convert any arsenic present into arsenate. 

Peroxides, organic Phosphorus (white) Potassium chlorate Potassium perchlorate Potassium permanganate Silver Acids (organic or mineral), avoid friction, store cold Air, oxygen Acids (see also chlorates) Acids (see also perchloric acid) Glycerol, ethylene glycol, benzaldehyde, sulphuric acid Acetylene, oxalic acid, tartaric acid, fulminic acid (produced in ethanol — nitric acid mixtures), ammonium compounds... 

Boron (finely divided forms) reacts violently with cone, acid and may attain incandescence. The vapour of phosphorus, heated in nitric acid in presence of air, may ignite. Boron phosphide ignites with the cone, acid [1], Silicon crystallised from its eutectic with aluminium reacts violently with cone, acid [2], arsenic may react violently with the fuming acid, and finely divided carbon similarly with cone, acid [3], Use of cone, acid to clean a stainless steel hose contaminated with phosphorus led to an explosion [4],... 

Tetraphosphorus iodide ignites in contact with cold cone, nitric acid, and phosphorus trichloride explodes with nitric (or nitrous) acid. 

Although the massive metal is relatively inert, when powdered it becomes very reactive. The dry powder may react explosively at elevated temperatures with nitrogen, phosphorus, oxygen, sulfur and other non-metals. The halogens react similarly, and in contact with hot cone, nitric acid and other oxidants it may explode (often after a delay with nitric acid). The powder is pyrophoric and readily ignitable by friction, heat or static sparks, and if dry bums fiercely. Presence of... 

A large number of reagents are available for the preparation of nitro PAHs. These include fuming nitric acid in acetic acid (20) or acetic anhydride (13), sodium nitrate in trifluoroacetic acid (21) or trifluoroacetic acid and acetic anhydride (17), dinitrogen tetroxide in carbon tetrachloride (22), sodium nitrate in trimethyl phosphate and phosphorus pentoxide (23), and nitronium tetrafluoroborate in anhydrous acetonitrile (24). Alternative approaches must be used to synthesize nitro PAHs substituted at positions other than the most reactive carbon. For instance,... 

Bromoacetic acid has been prepared by direct bromination of acetic acid at elevated temperatures and pressures,2-3-4 or with dry hydrogen chloride as a catalyst 6 and with red phosphorus as a catalyst with the formation of bromoacetyl bromide.6-7-8-9-19 Bromoacetic acid has also been prepared from chloroacetic acid and hydrogen bromide at elevated temperatures 6 by oxidation of ethylene bromide with fuming nitric acid 7 by oxidation of an alcoholic solution of bromoacetylene by air 8 and from ethyl a,/3-dibromovinyl ether by hydrolysis.9 Acetic acid has been converted into bromoacetyl bromide by action of bromine in the presence of red phosphorus, and ethyl bromoacetate has been... 

A fertilizer that provides both phosphorus and nitrogen is prepared by the reaction of calcium phosphate and nitric acid. 

Copper(II) sulfate Cumene hydroperoxide Cyanides Cyclohexanol Cyclohexanone Decaborane-14 Diazomethane 1,1-Dichloroethylene Dimethylformamide Hydroxylamine, magnesium Acids (inorganic or organic) Acids, water or steam, fluorine, magnesium, nitric acid and nitrates, nitrites Oxidants Hydrogen peroxide, nitric acid Dimethyl sulfoxide, ethers, halocarbons Alkali metals, calcium sulfate Air, chlorotrifluoroethylene, ozone, perchloryl fluoride Halocarbons, inorganic and organic nitrates, bromine, chromium(VI) oxide, aluminum trimethyl, phosphorus trioxide... 

Nitrites Nitrobenzene Nitroethane Nitrogen trichloride Organic nitrites in contact with ammonium salts, cyanides Nitric acid, nitrous oxide, silver perchlorate Hydroxides, hydrocarbons, metal oxides Ammonia, As, hydrogen sulfide, nitrogen dioxide, organic matter, ozone, phosphine, phosphorus, KCN, KOH, Se, dibutyl ether... 

Phosphorus pentafluoride Phosphorus pentasulfide Phosphorus pentoxide Phosphorus, red Phosphorus tribromide Phosphorus bichloride Water or steam Air, alcohols, water Formic acid, HF, inorganic bases, metals, oxidants, water Organic materials Potassium, ruthenium tetroxide, sodium, water Acetic acid, aluminum, chromyl dichloride, dimethylsulfoxide, hydroxylamine, lead dioxide, nitric acid, nitrous acid, organic matter, potassium, sodium water... 

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