Sodium hydrogen phosphates decompositions

In the oxidation of arsenic(iii) in perchlorate media the reaction order of less than unity with respect to reductant is interpreted in terms of the formation of an unstable 1 1 intermediate. Activation parameters are essentially constant (Ea = 9.3 0.5 kcal mol ) at both high (excess) and low [Cr " ] and the rate is increased on addition of sodium hydrogen phosphate. This latter observation may reflect an acid-catalytic route described earlier. The mechanism at low [Cr T with reductant in excess is considered to involve the rate-determining decomposition of the 1 1 complex to give Cr and an arsonium species of the type... 

Monobasic sodium phosphate is chemically stable, although it is slightly deliquescent. On heating at 100°C, the dihydrate loses all of its water of crystallization. On further heating, it melts with decomposition at 205°C, forming sodium hydrogen pyrophosphate, Na2H2P20y. At 250°C it leaves a final residue of sodium metaphosphate, NaPOs. 

Ferrous pyrophosphate, Fe2P207, is obtained 5 as an unstable white powder by double decomposition of ferrous sulphate and sodium pyrophosphate by heating ferrous orthophosphate and by reduction of ferric phosphate with hydrogen. Upon exposure to air it turns green and ultimately brown. 

LAPIS INFERNALIS (7761-88-8) A powerful oxidizer. Forms friction- and shock-sensitive compounds with many materials, including acetylene, anhydrous ammonia (produces compounds that are explosive when dry), 1,3-butadiyne, buten-3-yne, calcium carbide, dicopper acetylide. Contact with hydrogen peroxide causes violent decomposition to oxygen gas. Violent reaction with chlorine trifluoride, metal powders, nitrous acid, phosphonium iodide, red or yellow phosphorus, sulfur. Incompatible with acetylides, acrylonitrile, alcohols, alkalis, ammonium hydroxide, arsenic, arsenites, bromides, carbonates, carbon materials, chlorides, chlorosulfonic acid, cocaine chloride, hypophosphites, iodides, iodoform, magnesium, methyl acetylene, phosphates, phosphine, salts of antimony or iron, sodium salicylate, tannic acid, tartrates, thiocyanates. Attacks chemically active metals and some plastics, rubber, and coatings. 

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