Distillation receiving flask

Color photo of a keugelrohr distillation receiving flask full of DMT crystals. 

A sample of wheat weighing 1.2461 g was analyzed for protein nitrogen by the Kjeldahl procedure, with excess H3BO3 in the distillate receiving flask. Calculate the percentage of nitrogen if 13.19 ml of 0.0962 M HCl was required to the bromocresol green end point. Answer 1.426%. 

B is an arrangement for gaging the rate of flow of the acid and is provided with a side tube for the purpose of introducing a stream of CO2. C is a distilling flask provided with a delivery tubej thermometer welli and aide tube connected to a water condenser. D is the distillate-receiving flask. 

Fractional Distillation under Reduced Pressure. One great disadvantage of the simple vacuum-distillation apparatus shown in Fig. 12(a) is that, if more than one fraction distils, the whole process has to be stopped after collecting each consecutive fraction, in order to change the receiver F. This may be overcome by replacing the simple receiving flask F by a pig (Fig. 13) which collects consecutive... 

Ethyl bromide soon distils over, and collects as heavy oily drops under the water in the receiving flask, evaporation of the very volatile distillate being thus prevented. If the mixture in the flask A froths badly, moderate the heating of the sand-bath. When no more oily drops of ethyl bromide come over, pour the contents of the receiving flask into a separating-funnel, and carefully run oflF the heavy lower layer of ethyl bromide. Discard the upper aqueous layer, and return the ethyl bromide to the funnel. Add an equal volume of 10% sodium carbonate solution, cork the funnel securely and shake cautiously. Owing to the presence of hydrobromic and sulphurous acids in the crude ethyl bromide, a brisk evolution of carbon dioxide occurs therefore release the... 

Remove the condenser, then with the aid of a funnel add the water slowly, keep stirring. If the solution is too hot the water will evaporate and make a big mess. As the water is added you will notice that loads of stodgy crapp will form, this is normal, connect the condenser for the distillation with a receiving flask at least 500ml in capacity. 

Setup your glassware for simple distillation with a claisen adapter, three way adapter, pressure-equalized addition funnel, water cooled condenser, vacuum adapter and receiver flask to catch any condensed solvent vapors. 

When the removal of the ether is complete, the condenser is drained of water and the receiving flask is immersed in an ice bath. The condenser is heated by steam, if necessary, to prevent solidification of the distillate in the condenser. The distillation is resumed affording e i/o-tetrahydrodicyclopentadiene, bp 191-193, about 50 g (98%). The melting point varies with the purity of the starting diene but is usually above 65. ... 

The mixture is filtered into a 500-ml round-bottom flask, and methanol and water are removed by distillation under vacuum (bath temperature 50-60°) until the residual amine oxide hydrate solidifies. The flask is fitted with a magnetic stirrer and a short Vigreux column, and the receiving flask is cooled in a Dry Ice-acetone bath. The flask... 

The apparatus consists of a 100-ml distilling flask equipped with a dropping funnel and arranged for distillation through an efficient condenser. The condenser is connected to two receiving flasks in series, the second of which contains 20-30 ml of ether. The inlet tube of the second receiver dips below the surface of the ether and both receivers are cooled in ice baths. All connections in the setup are made with bored cork stoppers and all glass tubing is fire polished (Fig. 17.1). 

If an emulsion has formed, it may be broken by acidifying with hydrochloric acid, whereupon two clear layers are obtained. The benzene solution may be dried and then fractionated or preferably, it may be steam distilled. In the latter case it is transferred to a r-1. Claisen flask, the flask is set in an oil bath (Note 3) and the benzene distilled. Steam is then passed in, and after the last of the benzene is removed, the p-bromodi-phenyl distils with the steam. The temperature of the oil bath is held at 170° in order to hasten the distillation. The product solidifies in the condenser and receiving flask. There is obtained 23-24 g. of -bromodiphenyl which melts at 85-86.5°. 

Adipic acid, 146.1 g (1.0 mol), and 186.2 g (3 mol) of 1,2-ethanediol are weighed into a 500-mL glass reactor equipped with a mechanical stirrer, a nitrogen inlet, and a distillation head connected to a condenser and a receiver flask. The reactor is placed in a salt bath preheated at 180°C and the temperature is then raised gradually to 220°C (see note at end of procedure) until the greater part of water has been removed (3 h). The reactor is cooled down to 160°C and vacuum is applied slowly to about 0.07 mbar (30 min). Excess free 1,2-ethanediol begins to distill and temperature is raised gradually to 190°C (90 min). The reaction is continued for an additional 1 h. Pressure is then ramped to atmospheric widi a... 

The submitters recommend that the solvent be distilled under nitrogen into a two-necked receiving flask fitted with a three-way stopcock. The receiving flask is separated from the distillation apparatus under a rapid nitrogen flow and fitted quickly with a rubber septum. The solvent is then transferred to the reaction vessel by needlestock techniques. 

Diazomethane Follow essentially Aldrich Chemical Company s procedure for the Preparation of ethereal-alcoholic solution of diazomethane A 25-mL volume of ethanol is added to a solution of 5 g of potassium hydroxide in 8 mL of water in a 100-mL distillation flask fitted with a dropping funnel and a distillation condenser. The lower end of the condenser extends through and just below the neck of a 250-mL Erlenmeyer receiving flask, the latter being cooled in an ice-bath. The distillation flask containing the alkaline solution is heated in a water-bath to 65 °C and the contents of the flask are agitated with a magnetic stirrer. A solution of... 

Dining removal of free iodine from hydriodic acid by distillation from red phosphorus, phosphine was produced. When air was admixed by changing the receiver flask, an explosion occurred. Omission of distillation by boiling the reactants in inert atmosphere, and separating the phosphorus by fitration through a sintered... 

In the meantime, a mixture of 79 g. (0.55 mole) of cuprous bromide (Note 3) and 80 ml. (0.6 mole) of 48% hydrobromic acid (Note 1) is heated to boiling in a 5-1. round-bottomed thrcc-necked flask, equipped with a condenser set for distillation and provided with a 2-1. receiving flask, a steam inlet tube closed by a screw clamp, and a separatory funnel. About one-fourth of the diazonium solution is transferred to the separatory funnel, without filtration, and immediately run into the cuprous bro-mide-hydrobromic acid solution, which is kept boiling over a free flame, at such a rate that boiling is continuous. When the separatory funnel is nearly empty a further portion of the cold... 

At the end of the heating period the contents of the flask will have solidified. To the cold mixture 40 ml. of water is added to hydrolyze the potassium methoxide and precipitate the pyrimidine the fine crystals are filtered and dried. The crude product is placed in a 500-ml. distilling flask with 250 ml. of purified kerosene (Note 3). On distilling the kerosene, the pyrimidine codistils and solidifies in the receiving flask to a snow-white mass of crystals. These are filtered, washed well with petroleum ether, and dried in an oven at 100°. The yield of pure material, melting at 182-183°, is 27.5-28.7 g. (67-70%) (Note 4). 

Upon cooling to room temperature, a gray precipitate forms and the reaction is quenched with 220 mL of saturated, aqueous ammonium chloride. The resulting mixture is poured into a 1-L separatory funnel and extracted with 220 mL of diethyl ether. The organic fraction is washed two times with 100 mL of water, and once with 100 mL of brine, dried over magnesium sulfate, filtered, and concentrated under reduced pressure to provide 44.1 g of crude product as a pale yellow oil. Purification of this material by bulb-to-bulb distillation (140-145°C, 0.5 mm) (Note 11) into a chilled (-78°C) receiving flask yields 41.0 g (92%) of 2 as a clear, colorless oil (Note 12). 

A 1-1., three-necked, round-bottomed flask equipped with a Trubore stirrer, a pressure-equalizing dropping funnel, and a reflux condenser with a drying tube is charged with 350 ml. of acetonitrile (Note 1) and 106.4 g. (0.41 mole) of triphenylphos-phine (Note 2). The flask is cooled in an ice-water bath (Note 3), and 64 g. (0.40 mole) of bromine is added dropwise over a period of ca. 15-20 minutes (Notes 4 and 5). The ice-water bath is removed, and a solution of 54 g. (0.40 mole) of cinnamyl alcohol in 50 mi. of acetonitrile is added in portions over a period of 5-10 minutes with continued stirring (Note 6). The solvent is removed by distillation with the use of a water aspirator (30-40 mm.) and an oil bath until the bath temperature reaches 120°. The water aspirator is replaced by a vacuum pump and the water-cooled condenser with an air condenser, and the distillation is continued with rapid stirring (Notes 7, 8, and 9). Most of the product (Note 10) distills at 91-98° (2-4 mm.), and about 59 g. of product crystallizes in the receiving flask (63-75% yield) (Note 11). 

If at any time during the distillation of the sulfur trioxide, crystals of solid sulfur trioxide form in the condenser or receiving flask, they may be melted by careful local heating with a propane torch flame or by running hot water through the condenser jacket. The water in the condenser should be above 23° C during distillation of sulfur trioxide to prevent crystallization of sulfur trioxide polymers. 

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