Water, acid hygroscopic

The rate of hydrolysis of DMAC is very low, but increases somewhat in the presence of acids or bases. DMAC is a stable compound, but is mildly hygroscopic and desiccation and/or dry nitrogen blanketing of storage vessels are sometimes used to reduce water pick-up. In the absence of water, acids, or bases, DMAC is stable at temperatures up to its hoiling point at atmospheric pressure. Its greater stability enables more economical recovery by distillation relative to that of other similar solvents. 

The purified tetraethyl pyrophosphate is a colorless, odorless, water-soluble, hygroscopic liquid (24, 4 )- It possesses a very high acute toxicity (28), exceeding that of parathion, and is rapidly absorbed through the skin. There is no spray-residue problem, however, for tetraethyl pyrophosphate hydrolyzes even in the absence of alkali to nontoxic diethyl phosphoric acid. Hall and Jacobson (24) and Toy (47) have measured its rate of hydrolysis, which is a first-order reaction. Its half-life at 25° C. is 6.8 hours and at 38° C. is 3.3 hours. Coates (10) determined the over-all velocity constant at 25° C. k = 160 [OH-] + 1.6 X 10 3 min.-1 Toy (47) has described an elegant method for preparing this ester as well as other tetraalkyl pyrophosphates, based upon the controlled hydrolysis of 2 moles of dialkyl chlorophosphate ... 

Properties White crystals, transparent, hygroscopic. Mp (hydrate) 91C (decomposes) (anhydrous) d 3.842 (25C), mp 87.C soluble in alcohol, water, acids. 

Properties White crystals, hygroscopic. Bp 126C, mp 40C. Soluble in alcohol, water, acids. 

Properties Pure product is a blue-gray powder technical grade is a brown powder. D 7.24, mp 2270C. Insoluble in water soluble in acids, hygroscopic. Absorbs carbon dioxide from the air. 

GB is both miscible with water and hygroscopic, and like GA, is subject to both basic and acidic hydrolysis. The initial step in these hydrolyses involves loss of fluoride. Hydrolysis of the C-F bond in both GB and GD (soman) is accelerated by the presence of bleach (hypochlorite ion), although the process is complex and both pH and concentration dependent (Epstein et al., 1956). 

Tetragonal crystals. Slightly soluble in water, not hygroscopic, insoluble in dilute acids, soluble in strong alkalis, stable at red heat. 

Features Its prods, offer resist, to hydrolysis, solvs., oil and microbes, low temp, behavior, and transparency Properties APHA < 50 max. liq. sol. in most org. solvs. barely sol. in water m.w. 2000 120 sp.gr. 1.048 (60 C) soften, pt. 18C acid no. < 0.05 hyd. no. 52.9-59.7 flash pt. 204 C < 0.03% water Storage Hygroscopic protect from moisture and air dry nitrogen blanket should be applied to open containers before resealing PolyTHF 250 [BASF BASF AG]... 

Diethylethanolamine (Diethylaminoethanol, (CtHOrNCrHrOH). Di-ethylaminoethanol is a water-white, hygroscopic liquid which behaves chemically like the tertiary amines and alcohols. It is soluble in water, ethyl alcohol, methyl alcohol, ethyl ether, ethyl acetate, acetone, aromatic hydrocarbons, fixed oils, mineral oil, oleic acid, hot stearic acid, and hot paraffin and carnauba wa.xes, the last two solidifying when cooled. It is used in the manufacture of certain pharmaceuticals, such as procaine and "atabrine". It forms amine soaps with higher fatty acids, which are oil-soluble and useful as emulsifiers and textile lubricants. Its mild alkalinity makes it applicable as a neutralizing agent and a corrosion inhibitor. 

Polyplasdone . These polymers are completely insoluble in water, acids, alkalis and all organic solvents. As they are highly hygroscopic and able to swell rapidly in water without forming gels, they are also very efficient disintegrating agents. 

Regulatory FDA21CFR 136.110(c)(15), 172.846 Properties Cream-colored powd. readily disp. In hot oil, fat, or water acid no. 60-80 ester no. 150-190 31-34% total ladle add 3.5-5 0% Na Storage 12 mos. shelf life, best when used before 9 mos si. hygroscopic store In cool, dry location avoid temps, above 90 F at all limes keep containers well closed when not in use Panodan 120 Series [Danisco USA]... 

HOCHj CHjOH. Colourless, odourless, rather viscous hygroscopic liquid having a sweet taste, b.p. 197 C. Manufactured from ethylene chlorohydrin and NaHC03 solution, or by the hydration of ethylene oxide with dilute sulphuric acid or water under pressure at 195°C. Used in anti-freezes and coolants for engines (50 %) and in manufacture of polyester fibres (e.g. Terylene) and in the manufacture of various esters used as plasticizers. U.S. production 1979 1 900 000 tonnes. 

Benzene. Pure benzene (free in particular from toluene) must be used, otherwise the freezing-point is too low, and crystallisation may not occur with ice-water cooling alone. On the other hand, this benzene should not be specially dried immediately before use, as it then becomes slightly hygroscopic and does not give a steady freezing-point until it has been exposed to the air for 2-3 hours. Many compounds (particularly the carboxylic acids) associate in benzene, and molecular weights determined in this solvent should therefore be otherwise confirmed. 

Glacial Acetic Acid. Acetic acid is very hygroscopic, and its freezing-point is considerably affected by the water absorbed. Satisfactory results cannot be obtained with the apparatus shown in Fig. 79, p. 433, and a specially modified apparatus must be employed (see Nitrobenzene). 

Sulphonic acids are frequently crystalline solids, readily soluble in water and often hygroscopic. Because of the difficulty of isolation of the free acids, they are usually encountered as the alkah metal salts. 

Acetic acid containing less than 1% water is called glacial. It is hygroscopic and the freezing point is a convenient way to determine purity (7). Water is nearly always present in far greater quantities than any other impurity. Table 1 shows the freezing points for acetic acid-water mixtures. 

Bromoacetic acid [79-08-3] (BrCH2COOH), mol wt 138.96, C2H3Br02, occurs as hexagonal or rhomboidal hygroscopic crystals, mp 49°C, bp 208°C, 1.9335, 1-4804. It is soluble in water, methanol, and ethyl ether. Bromoacetic acid undergoes many of the same reactions as chloroacetic acid under... 

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