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Hydrogen fluoride boiling temperature

Clearly, ammonia, water, and hydrogen fluoride boil at significantly higher temperatures than methane. The N—H, O—H, and F—H bonds are far more polar than the C—H bond, owing to the high electronegativity of N, O, and F. [Pg.166]

Properties. Antimony pentafluoride [7783-70-2], SbF, is a colorless, hygroscopic, very viscous liquid that fumes ia air. Its viscosity at 20°C is 460 mPa-s(=cP) which is very close to the value for glycerol. The polymerization of high purity SbF at ambient temperature can be prevented by addition of 1% anhydrous hydrogen fluoride, which can be removed by distillation prior to the use of SbF. The pure product melts at 7°C (11), boils at 142.7°C,... [Pg.150]

Barium fluoride [7782-32-8] Bap2, is a white crystal or powder. Under the microscope crystals may be clear and colorless. Reported melting points vary from 1290 (1) to 1355°C (2), including values of 1301 (3) and 1353°C (4). Differences may result from impurities, reaction with containers, or inaccurate temperature measurements. The heat of fusion is 28 kj/mol (6.8 kcal/mol) (5), the boiling point 2260°C (6), and the density 4.9 g/cm. The solubiUty in water is about 1.6 g/L at 25°C and 5.6 g/100 g (7) in anhydrous hydrogen fluoride. Several preparations for barium fluoride have been reported (8—10). [Pg.155]

Isopropyl Fluoride.48 The procedure is the same as for ethyl fluoride except that the temperature is kept at 0°, and the ratio of hydrogen fluoride to propylene is held to 1.08. The yield is 61% isopropyl fluoride boils at —10.1°. [Pg.69]

Bis(pentafluorosulfanyl)amine is prepared in quantitative yield by the addition of hydrogen fluoride to SF5NSF4 (214). It is a colorless liquid that boils at 60.4°C, and it is stable in glass at room temperature. At elevated temperatures in the presence of alkali metal fluorides, it loses HF and forms SF5NSF4. It is a weak acid, which with large cations forms stable salts such as Ph4P+N(SF5)2 (229). [Pg.151]

The major drawback of the use of anhydrous hydrogen fluoride is its lower boiling point and volatility at ambient temperatures. Some of the state governments believe that storage of AHF is highly risky in populated areas and creates life and environmental threats. As a result, some refineries have been forced to switch from AHF to H2SO4 alkylation process. [Pg.664]

The reaction of phosgene with hydrogen fluoride offers a potentially attractive route to the synthesis of carbonyl difluoride. However, the hydrogen chloride co-product of the reaction, represented in Equation (13.4) has a boiling temperature (-83.1 C) very close to that of COFj (-84.6 "C). In addition, azeotrope formation occurs, so that the two materials are only separated with great difficulty using normal distillation techniques. Separation of the two materials may be affected using aliphatic nitriles (such as ethanenitrile) or aromatic hydrocarbons (such as toluene) in which HCl is more readily absorbed relative to COF j [629,630]. Alternatively, the separation may be affected by adsorption of the HCl onto a metal fluoride, SO 3 or PjOj, which do not react at all readily with the COFj [2069]. [Pg.568]

FOLLOW-UP PROBLEM 1 7.9 In a study of the chemistry of glass etching, an inorganic chemist examines the reaction between sand (Si02) and hydrogen fluoride at a temperature above the boiling point of water ... [Pg.564]

Benzotrifluoride 767 A slow stream of hydrogen fluoride (200 g) is introduced in 72 h into benzotrichloride (500 g) which is stirred at 0° in a copper flask fitted with a copper gas inlet tube that reaches to the bottom, a gas outlet tube, and a copper stirrer. Initially only HC1 is evolved, but this includes HF and benzotrifluoride in increasing amounts as reaction proceeds they are condensed out in a copper receiver cooled in ice-salt. The product in the flask and the condensate in the receiver are united and warmed to room temperature, then shaken with sodium fluoride to bind the HF. Filtration and distillation of the filtrate gives benzotrifluoride (300 g), b.p. 102.3°. Higher-boiling distillate contains partially chlorinated benzotrichloride and can be used in a new batch. [Pg.204]

Vinylidene fluoride, CH2=CF2, is obtained by the pyrolysis of 1,1-difluoro- 1-chloroethane, which in turn is produced from acetylene, vinylidene chloride, or 1,1,1-trichloroethane by reaction with hydrogen fluoride. Because of its low boiling temperature, —84°C, vinylidene fluoride is suspension or emulsion polymerized under pressure. Considerable head-head linkage quantities are produced in these polymerizations. [Pg.430]

Vinyl fluoride is obtained from the reaction of hydrogen fluoride with acetylene or ethylene. The free radical polymerization is carried out at pressures of 300 bar because of the low boiling temperature, —72°C, of the monomer. The polymer is partially crystalline and has similar properties to poly(ethylene), but the melting temperature, (200° C), is much higher and the weatherability is much better. [Pg.431]


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