Alkali iodides, reducing agents

Trihydrate, dark green, odorless crystals with bronze luster or cryst powder. Absorption max 668, 609 tint. One gram dissolves in about 25 ml water, about 65 ml alcohol sol in chloroform. In sol in ether. In aq soln it is decolorized by Zn dust and dil H2SOt, but color is restored on exposure to air and more rapidly upon addn of NH,OH, Forms double salts with many inorganic salts. Incompat Caustic alkali, dichromates, alkali iodides, reducing agents. 

In its solutions in liquid NIL. cesium is like the other alkali metals, a powerful reducing agent, so that in such solutions, titrations of cesium poly sulfide with cesium are made by eleclrumeiric methods. The solubility of cesium salts in liquid NHi increases markedly with the radius of an anion (the chloride. CsCI. 0.0227 moles per kg. the bromide. CsBr, 0.215 moles per kg. and the iodide. Csl. 5.84 moles per kg), though the values are less than for the corresponding rubidium compounds. 

The most employed reducing agents in the old tellurium chemistry were alkali sulphites or hydrogen sulphites, methyhnagnesium iodide and sodium sulphide hydrate. The last reagent is still used, together with the more recently introduced sodium borohydride, TUDO, hydrazine, samarium diiodide and sodium ascorbate. ... 

Ceric compounds are reduced to cerous very easily by such reagents as hydrogen peroxide in acid solution, sulfur dioxide, hydrochloric acid, oxalic acid, stannous chloride, ferrous sulfate, etc. The transformation of ceric oxide to a cerous salt requires the presence of the desired acid and a reducing agent, since CeC>2 is difficultly soluble in mineral acids. It may be accomplished by (1) nitric acid and hydrogen peroxide (2) hydroquinone and hydrochloric or sulfuric acids (3) hydrochloric acid and an alkali iodide. 

MERCURIC IODIDE or MERCURIC IODIDE, RED (7774-29-0) Hglj Aqueous solution is a weak reducing agent. Incompatible with acetylene, alkalis, ammonia, azides, chlorine dioxide, azides, bromides, calcium (amalgam formation), chlorides, cyanides, copper salts hydrogen... 

POTASSIUM lODATE (7758-05-6) KIO, Noncombustible solid but many chemical reactions can cause fire and explosions. A strong oxidizer. Reacts violently with many materials, including reducing agents, hydrides, nitrides, and sulfides combustible materials, organic substances, manganese dioxide, arsenic, finely divided metals or carbon materials, hydrides of alkali or alkaline earth metalss, metal cyanides, metal thiocyanates, phosphonium iodide, red phosphorus, sulfides, sulfur, xenon tetrafluoride. Forms explosive compounds with solid organic matter. Mixture of powdered aluminum forms heat-, friction-, and shock-sensitive explosive. Attacks chemically active metals (e.g, aluminum, copper, zinc, etc.). Thermal deconposition, at temperatures above 1040°F/560°C, releases toxic iodine fumes. 

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