MOIST

Viscosity references include Kestin, J. and J. H. Whitelaw, Int.J. Ht. Mass Tran. 7,11 (1964) 1245-1255 Studnokov, E. L.,Inz.-Fiz. Zhur. 19, 2 (1970) 338-340 Hochramer, D. and F. Munczak, Setzb. Ost. Acad. Wiss II175,10 (1966) 540-550. For thermal conductivity see, for instance. Mason, E. A. and L. Monchick, Humidity and Moisture Control in Science and Industry, Reinhold, New York, 1965 (257—272). 

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Hi at 500" C. Stable crystalline compound, gives LiOH and Hi with water (may ignite in moist atmosphere). Used as a source of Hi, as a reducing agent, and for the preparation of hydrides. 

CHjlCH COOH. Colourless liquid having an odour resembling that of ethanoic acid m.p. 13 C, b.p. I4I°C. Prepared by oxidizing propenal with moist AgO or treating -hy-droxypropionitrile with sulphuric acid. Slowly converted to a resin at ordinary temperatures. Important glass-like resins are now manufactured from methyl acrylate, see acrylic resins. Propenoic acid itself can also be polymerized to important polymers - see acrylic acid polymers. 

Silicon tetrachloride. S1CI4 m.p. — TO C, b.p. 57°C. Colourless liquid (Si plus CI2 followed by distillation). Hydrolyses in moist air or in water. 

In moist enviromnents, water is present either at the metal interface in the fonn of a thin film (perhaps due to condensation) or as a bulk phase. Figure A3.10.1 schematically illustrates another example of anodic dissolution where a droplet of slightly acidic water (for instance, due to H2SO4) is in contact with an Fe surface in air [4]. Because Fe is a conductor, electrons are available to reduce O2 at the edges of the droplets. 

The trichloride is obtained as a liquid, boiling point 349 K, when a jet of chlorine burns in phosphorus vapour. Care must be taken to exclude both air and moisture from the apparatus since phosphorus trichloride reacts with oxygen and is vigorously hydrolysed by water, fuming strongly in moist air. The hydrolysis reaction is ... 

This reaction is a useful test for a sulphite or for moist sulphur dioxide, which turns dichromate paper (filter paper soaked in potassium dichromate) from yellow to green. 

Sulphur oxide dichloride is a colourless liquid which fumes in moist air. It is hydrolysed by water to give a mixture of sulphurous and hydrochloric acids ... 

The presence of chloric(I) acid makes the properties of chlorine water different from those of gaseous chlorine, just as aqueous sulphur dioxide is very different from the gas. Chloric(I) acid is a strong oxidising agent, and in acid solution will even oxidise sulphur to sulphuric acid however, the concentration of free chloric(I) acid in chlorine water is often low and oxidation reactions are not always complete. Nevertheless when chlorine bleaches moist litmus, it is the chloric(I) acid which is formed that produces the bleaching. The reaction of chlorine gas with aqueous bromide or iodide ions which causes displacement of bromine or iodine (see below) may also involve the reaction... 

Any free bromine can be removed by passing the evolved gas through a U tube packed with glass beads covered with moist violet phosphorus (Figure 113). 

Properties—Hydrogen iodide is a colourless gas. It is very soluble in water and fumes in moist air (cf. hydrogen chloride), to give hydriodic acid. Its solution forms a constant boiling mixture (cf. hydrochloric and hydrobromic acids). Because it attacks mercury so readily, hydrogen iodide is difficult to study as a gas, but the dissociation equilibrium has been investigated. 

The reaction usually proceeds with explosive violence and a better method of preparation is to heat, gently, moist crystals of ethane-dioic acid (oxalic acid) and potassium chlorate(V) ... 

ChloricfVII) acid fumes in moist air and is very soluble in water, dissolving with the evolution of much heat. Several hydrates are known the hydrate HCIO4. H2O is a solid at room temperature and has an ionic lattice [HjO ] [CIO4]. 

Ammonia evolved in the cold (turns moist red litmus-paper blue). Methane may be evolved by stronger and more prolonged heating. 

Physical properties. Colourless liquids when pure, benzoyl chloride, CjHjCOCl, is frequently pale yellow. Acetyl chloride, CH3COCI, has a pungent odour, fumes in moist air and is immediately hydrolysed by cold water. Benzoyl chloride also has a pungent odour, is lachry matory, and is hydrolysed only slowly by cold water, in which it is insoluble. 

Much of the chloroform of commerce is obtained by the action of moist iron upon carbon tetrachloride the following preparation is, however, instructive. 

Methylene chloride CHjCl, b.p. 41°, is obtained as a by product in the com mercial preparation of chloroform by the reduction of carbon tetrachloride with moist iron and also as one of the products in the chlorination of methane it is a useful extraction solvent completely immiscible with water. 

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