Sodium phosphite

Besides Fe-, other reducing agents that may be used in conjunction with H2O2 are aliphatic amines, Na2S203 thiourea, ascorbic acid, glyoxal, sulfuric acid, NaHSOs, sodium nitrite, ferric nitrate, peroxidase, AgNOs, tartaric acid, hydroxylamine, ethylene sulfate, sodium phosphite, formic acid, ferrous ammonium sulphate, acetic acid, ferrous sulphate, and HNO2, etc,... 

What is the oxidation number of phosphorus in sodium phosphite, Na3P03 In the dihydrogen phosphate ion ... 

The mechanism of formation of PCBs from the trichlorobenzene solvent involves hydrogen abstraction by the urea present, leading to the formation of trichlorophenyl radicals. Two such radicals can then combine (Scheme 2.2) to form a PCB molecule (2.36). This reaction can be suppressed by adding antioxidants such as hydroquinone or sodium phosphite to yield hydrogen (H ) radicals, which convert (Scheme 2.3) the trichlorophenyl radicals back to the parent substance (2.37). 

It was subsequently shown that dissolution of y-irradiated sodium phosphite crystals (Na2HP03.5HzO) in aqueous MNP gives the spin adduct of the PO - radical dianion (aN = 13.4 ar = 12.0 G) (Adevik and Lagercrantz, 1970). 

Nr-soln., 0-021 per cent, of sodium phosphite is hydrolyzed. A. Italiener gave for the H-ion cone. 

H. Rose found the syrupy liquid crystallized when kept in vacuo. C. A. Wurtz said the salt can be dried at 280° without decomposition. P. L. Dulong said that the salt is deliquescent in air, and insoluble in alcohol. According to A. Gutmann, a cold or boiling soln. of sodium thiosulphate does not act on sodium or potassium phosphite—vide the arsenites. N. N. Mittra and N. R. Dhar found that the reaction with mercuric chloride and sodium phosphite as primary reactions is hastened by the simultaneous reaction of mercuric chloride with sodium arsenite or arsenious acid. 

Palladium black catalvtically assists the oxidation of sodium dihydrogen hypophosphite solution to sodium phosphite, thus ... 

To study these reactions use a freshly prepared (Mm solution of sodium phosphite Na2HP03.5H20. 

Sodium phosphite (OTm). Dissolve 2-16 g sodium phosphite pentahydrate, Na2HP03.5H20, in water and dilute the solution to 100ml. The reagent should be prepared freshly. 

Sodium peroxide, Na202 Sodium phosphite, Na2HP03.5H20... 

Sodium phosphites.—Disodium hydrogen phosphite, Na2HP03,5H20, is obtained by concentration of a solution of phosphorous acid neutralized with sodium carbonate, and over sulphuric acid changes to the anhydrous salt. The pentahydrate is very deliquescent. The anhydrous salt melts at 53° C., and above this temperature is oxidized to sodium phosphate, with evolution of phosphine.7 The heat of formation from the elements is 285 1 Cal.,8 and from the acid and sodium hydroxide in solution 28 45 Cal.9 The heat of hydration of the anhydride to the pentahydrate is 18 7 Cal. 

Phosphorous acid is a weak acid, which forms two series of salts. Ordinary sodium phosphite is NagHPOg SHgO. Sodium hydrogen phosphite, NaHHPOa SHoO, also exists, but the third hydrogen atom cannot be replaced by a cation. It was mentioned in Chapter 20 that the non-acidic character of this third hydrogen atom is due to its attachment directly to the phosphorus atom, rather than to an oxygen atom ... 

Write a chemical equation for the reduction of Ag f by a solution of sodium phosphite. 

The compmmd formed may be called methyl phosphite by analogy to sodium phosphite, or better, phosphorus methoxide. In order to keep the rate of side reactions as slow as possible, it is necessary to add the iodine in small portions and to keep the temperature in the beginning below 20°. 

Raney nickel liberates hydrogen from water in the presence of sodium hypo-phosphite, which becomes oxidized to sodium phosphite. This reducing system in aqueous acetic acid or aqueous acetic acid-pyridine reduces nitriles to aldehydes at room temperature and pressure yields 50-90%. ... 

Sturtz, G., The action of sodium phosphites on the co-halogenated ketones. Bull. Soc. Chim. Fr, 2333, 1964. 

Arbuzov, B.A., Vinogradova, V.S.. Polezhaeva. N.A., and Shamsutdinova, A.K., Esters of P-oxophos-phonic acids. Part 12. Structure of reaction products of some a-halo ketones of the aromatic series with tnethyl phosphite and diethyl sodium phosphite, Izv. Akad. Nauk SSSR, Ser Khim., 1380, 1963 Bull. Acad. Sci. USSR, Div. Chem. Sci. (Engl. Transl.), 1257, 1963. 

Arbuzov, B.A., and Lugovkin, B.P., Action of triethyl phosphite and diethyl sodium phosphite on some dihalo derivatives, Zh. Obshch. Khim., 21, 99, 1951 Chem. Abstr, 45, 7002e, 1951. 

Chavane, V., and Rumpf, P, The abnormal reaction of a-halogenated carboxyhc esters with dialkyl sodium phosphites, C.R. Acad. Sci. (Paris). 225, 1322, 1947 Chem. Abstr, 42, 2575g, 1948. 

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