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Temperature of rooms

Average temperature of room temperature and warm water ... [Pg.307]

The reason for the use of methyl or ethyl nitrite in this reaction is two-fold. First of all, the matching alcohols are very easily picked up at the hardware or liquor stores. The second reason is that the methyl and ethyl nitrites give a little higher yields at lower temperatures. For example, methyl nitrite gives 90% yield of phenylacetone at a reaction temperature of room temperature. Butyl nitrite, on the other hand, gives a 87% yield at a temperature of SSoC. The possibility of running a batch at room temperature makes bathtub size production easy to envision. [Pg.44]

In addition, thermal comfort is also an important factor in buildings this is linked to the following four physical factors the ambient room air temperature, the average temperature of room-enclosing surfaces, moisture content and movement of air within the room. [Pg.51]

The Au cluster-PE thin films were prepared with the ICB-TOFMS system. First, a PE thin film is deposited on amorphous carbon thin films of the TEM grids at substrate temperatures of room temperature and 90 C. Then the Au clusters and atoms were deposited. Finally, the PE film was deposited again. The thin-film structures are showed in Fig. 13, which shows TEM micrographs for the substrate at room temperature and their electron diffraction patterns. [Pg.742]

All calorimeters consist of the calorimeter proper and its surround. This surround, which may be a jacket or a batii, is used to control tlie temperature of the calorimeter and the rate of heat leak to the environment. For temperatures not too far removed from room temperature, the jacket or bath usually contains a stirred liquid at a controlled temperature. For measurements at extreme temperatures, the jacket usually consists of a metal block containing a heater to control the temperature. With non-isothemial calorimeters (calorimeters where the temperature either increases or decreases as the reaction proceeds), if the jacket is kept at a constant temperature there will be some heat leak to the jacket when the temperature of the calorimeter changes. [Pg.1901]

Similar considerations have been exploited for the systematic analysis of room-temperature and molecular-beam IR spectra in temis of intramolecular vibrational relaxation rates [33, 34, 92, 94] (see also chapter A3.13 V... [Pg.2141]

Dissolve 36 g. of sodium hydroxide in 160 ml. of water contained in a 500 ml. conical flask, and chill the stirred solution to 0-5° in ice-water. Now add io-8 ml. (32-4 g.) of bromine slowly to the stirred solution exercise care in manipulating liquid bromine ) during this addition the temperature rises slightly, and it should again be reduced to 0-5°. Add a solution of 12 g. of acetamide in 20 ml. of water, in small portions, to the stirred hypobromite solution so that the temperature of the mixture does not exceed 20° the sodium acet-bromoamide is thus obtained in the alkaline solution. Now remove the flask from the ice-water, and set it aside at room temperature for 30 minutes. [Pg.128]

Add 25 g. of finely-powdered, dry acetanilide to 25 ml. of glacial acetic acid contained in a 500 ml. beaker introduce into the well-stirred mixture 92 g. (50 ml.) of concentrated sulphuric acid. The mixture becomes warm and a clear solution results. Surround the beaker with a freezing mixture of ice and salt, and stir the solution mechanically. Support a separatory funnel, containing a cold mixture of 15 -5 g. (11 ml.) of concentrated nitric acid and 12 -5 g. (7 ml.) of concentrated sulphuric acid, over the beaker. When the temperature of the solution falls to 0-2°, run in the acid mixture gradually while the temperature is maintained below 10°. After all the mixed acid has been added, remove the beaker from the freezing mixture, and allow it to stand at room temperature for 1 hour. Pour the reaction mixture on to 250 g. of crushed ice (or into 500 ml. of cold water), whereby the crude nitroacetanilide is at once precipitated. Allow to stand for 15 minutes, filter with suction on a Buchner funnel, wash it thoroughly with cold water until free from acids (test the wash water), and drain well. Recrystallise the pale yellow product from alcohol or methylated spirit (see Section IV,12 for experimental details), filter at the pump, wash with a httle cold alcohol, and dry in the air upon filter paper. [The yellow o-nitroacetanihde remains in the filtrate.] The yield of p-nitroacetanihde, a colourless crystalline sohd of m.p. 214°, is 20 g. [Pg.581]

Make a thin paste of 21 5 g. of finely-powdered o-tolidine (a commercial product) with 300 ml. of water in a 1-litre beaker, add 25 g. (21 ml.) of concentrated hydrochloric acid, and warm until dissolved. Cool the solution to 10° with ice, stir mechanically, and add a further 25 g. (21 ml.) of concentrated hydrochloric acid (1) partial separation of o tolidine dihydrochloride will occur. Add a solution of 15 g, of sodium nitrite in 30 ml. of water as rapidly as possible, but keep the temperature below 15° a slight excess of nitrous acid is not harmful in this preparation. Add the clear, orange tetrazonium solution to 175 ml. of 30 per cent, hypophosphorous acid (2), and allow the mixture to stand, loosely stoppered, at room temperature for 16-18 hours. Transfer to a separatory funnel, and remove the upper red oily layer. Extract the aqueous layer with 50 ml, of benzene. Dry the combined upper layer and benzene extract with anhydrous magnesium sulphate, and remove the benzene by distillation (compare Fig. II, 13, 4) from a Widmer or similar flask (Figs. II, 24, 3-5) heat in an oil bath to 150° to ensure the removal of the last traces of benzene. Distil the residue at ca. 3 mm. pressure and a temperature of 155°. Collect the 3 3 -dimethyldiphenyl as a pale yellow liquid at 114-115°/3 mm. raise the bath temperature to about 170° when the temperature of the thermometer in the flask commences to fall. The yield is 14 g. [Pg.616]

In a 500 ml. wide-mouthed reagent bottle place a cold solution of 25 g. of sodium hydroxide in 250 ml. of water and 200 ml. of alcohol (1) equip the bottle with a mechanical stirrer and surround it with a bath of water. Maintain the temperature of the solution at 20-25°, stir vigorously and add one-half of a previously prepared mixture of 26-5 g. (25 -5 ml.) of purebenzaldehyde (Section IV,115) and 7 -3 g. (9-3 ml.) of A.R. acetone. A flocculent precipitate forms in 2-3 minutes. After 15 minutes add the remainder of the benzaldehyde - acetone mixture. Continue the stirring for a further 30 minutes. Filter at the pump and wash with cold water to eliminate the alkali as completely as possible. Dry the solid at room temperature upon filter paper to constant weight 27 g. of crude dibenzalacetone, m.p. 105-107°, are obtained. Recrystallise from hot ethyl acetate (2-5 ml. per gram) or from hot rectified spirit. The recovery of pure dibenzalacetone, m.p. 112°, is about 80 per cent. [Pg.717]

Place 200 g. (172 -5 ml.) of redistilled furfural (1) in a 1 litre beaker, provided with a mechanical stirrer and surrounded by an ice bath. Start the stirrer and, when the temperature has fallen to 5-8°, add a solution of 50 g. of sodium hydroxide in 100 ml. of water from a separatory funnel at such a rate that the temperature of the reaction mixture does not rise above 20° (20-25 minutes) continue the stirring for a further 1 hour. Much sodium furoate separates during the reaction. Allow to cool to room temperature, and add just enough water to dissolve the precipitate (about 65 ml.). Extract the solution at least five times with 60 ml. portions of ether in order to remove the furfuryl alcohol the best results are obtained by the use of the continuous extraction apparatus (charged with 350 ml. of ether) depicted in Fig. //, 44, 2. Keep the aqueous layer. Dry the ethereal extract with a httle anhydrous... [Pg.832]

In a 500 ml. three-necked flask, equipped with a mechanical stirrer, thermometer and dropping funnel, place 300 ml. of 88-90 per cent, formic acid and add 70 ml. of 30 per cent, hydrogen peroxide. Then introduce slowly 41 g. (51 ml.) of freshly distilled cyclohexene (Section 111,12) over a period of 20-30 minutes maintain the temperature of the reaction mixture between 40° and 45° by cooling with an ice bath and controlling the rate of addition. Keep the reaction mixture at 40° for 1 hour after all the cyclohexene has been added and then allow to stand overnight at room temperature. Remove most of the formic acid and water by distillation from a water bath under reduced pressure. Add an ice-cold solution of 40 g. of sodium hydroxide in 75 ml. of water in small portions to the residual mixture of the diol and its formate take care that the tempera... [Pg.894]

Amino-3 5-diiodobenzoic acid. In a 2 litre beaker, provided with a mechanical stirrer, dissolve 10 g. of pure p-aminobenzoic acid, m.p. 192° (Section IX,5) in 450 ml. of warm (75°) 12 -5 per cent, hydrochloric acid. Add a solution of 48 g. of iodine monochloride (1) in 40 ml. of 25 per cent, hydrochloric acid and stir the mixture for one minute during this time a yellow precipitate commences to appear. Dilute the reaction mixtiue with 1 litre of water whereupon a copious precipitate is deposited. Raise the temperature of the well-stirred mixture gradually and maintain it at 90° for 15 minutes. Allow to cool to room tempera-tiue, filter, wash thoroughly with water and dry in the air the yield of crude acid is 24 g. Purify the product by dissolving it in dilute sodium hydroxide solution and precipitate with dilute hydrochloric acid the yield of air-dried 4-amino-3 5-diiodobenzoic acid, m.p. >350°, is 23 g. [Pg.973]

Once the reaction mix has cooled after reflux, 500mL of room temperature dHsO can be added and the whole solution extracted with DCM. The DCM layer is separated and the solvent removed by distillation to give the li-nitropropene as an oil of all things. This oil can then be recrystallized in hot methanol just like the crystalline form was [38]. [Pg.130]

The authors say that the 5 day reaction time at room temp can be accelerated by raising the temperature of the reaction. But they did not specify how much heat or how much time would be reduced. [Pg.139]


See other pages where Temperature of rooms is mentioned: [Pg.269]    [Pg.172]    [Pg.84]    [Pg.94]    [Pg.379]    [Pg.45]    [Pg.139]    [Pg.281]    [Pg.269]    [Pg.172]    [Pg.84]    [Pg.94]    [Pg.379]    [Pg.45]    [Pg.139]    [Pg.281]    [Pg.228]    [Pg.427]    [Pg.269]    [Pg.1839]    [Pg.3000]    [Pg.167]    [Pg.196]    [Pg.27]    [Pg.301]    [Pg.348]    [Pg.613]    [Pg.854]    [Pg.873]    [Pg.916]    [Pg.916]    [Pg.977]    [Pg.1004]    [Pg.102]    [Pg.141]    [Pg.134]    [Pg.238]    [Pg.14]    [Pg.50]    [Pg.52]    [Pg.137]    [Pg.168]    [Pg.177]   
See also in sourсe #XX -- [ Pg.131 , Pg.162 , Pg.185 , Pg.189 , Pg.194 , Pg.195 , Pg.197 , Pg.202 , Pg.208 , Pg.211 , Pg.213 , Pg.214 , Pg.219 , Pg.225 , Pg.228 , Pg.230 ]




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