Carbon concentration cautions

Concentrated sulfuric Silver nitrate Citrates, C6H507 Evolution of carbon dioxide and carbon monoxide (caution highly toxic) White precipitate of silver citrate that is soluble in dilute ammonia solution... 

Silver nitrate Concentrated sulfuric acid, hot Mercury (I) nitrate Copper sulfide White precipitate of silver cyanide Liberation of carbon monoxide (caution highly toxic) Gray precipitate of mercury Formation of colorless tetracyanocuprate (I) ions this test can be done on a section of filter paper... 

Dissolve 180 g. of commercial ammonium carbonate in 150 ml. of warm water (40-50°) in a 700 ml. flask. Cool to room temperature and add 200 ml. of concentrated ammonia solution (sp. gr. 0 88). Introduce slowly, with swirling of the contents of the flask, a solution of 50 g. of chloroacetic acid (Section 111,125) in 50 ml. of water [CAUTION do not allow chloroacetic acid to come into contact with the skin as unpleasant burns will result]. Close the flask with a solid rubber stopper and fix a thin copper wire to hold the stopper in place do not moisten the portion of the stopper in contact with the glass as this lubrication will cause the stopper to slide out of the flask. Allow the flask to stand for 24-48 hours at room temperature. Transfer the mixture to a distilling flask and distil in a closed apparatus until the volume is reduced to 100-110 ml. A convenient arrangement is to insert a drawn-out capillary tube into the flask, attach a Liebig s condenser, the lower end of which fits into a filter flask (compare Fig.//, 1) and connect the... 

In a 500 ml. flask, fitted with a reflux condenser, place 53 g. of 1-chloro-methylnaphthalene (Section IV.23), 84 g, of hexamethylenetetramine and 250 ml. of 1 1 acetic acid [CAUTION 1-Chloromethylnaphtha-lene and, to a lesser degree, a-naphthaldehyde have lachrymatory and vesicant properties adequate precautions should therefore be taken to avoid contact with these substances.] Heat the mixture under reflux for 2 hours it becomes homogeneous after about 15 minutes and then an oil commences to separate. Add 100 ml. of concentrated hydrochloric acid and reflux for a further 15 minutes this will hydrolyse any SchifiF s bases which may be formed from amine and aldehyde present and will also convert any amines into the ether-insoluble hydrochlorides. Cool, and extract the mixture with 150 ml. of ether. Wash the ether layer with three 50 ml. portions of water, then cautiously with 50 ml. of 10 per cent, sodium carbonate solution, followed by 50 ml. of water. Dry the ethereal solution with anhydrous magnesium sulphate, remove the ether by distillation on a steam bath, and distil the residue under reduced pressure. Collect the a-naphthaldehyde at 160-162718 mm. the yield is 38 g. 

Black Liquor Soap Acidulation. Only two-thirds of a typical black Hquor soap consists of the sodium salts of fatty acids and resin acids (rosin). These acids are layered in a Hquid crystal fashion. In between these layers is black Hquor at the concentration of the soap skimmer, with various impurities, such as sodium carbonate, sodium sulfide, sodium sulfate, sodium hydroxide, sodium Hgnate, and calcium salts. This makes up the remaining one-third of the soap. Cmde tall oil is generated by acidifying the black Hquor soap with 30% sulfuric acid to a pH of 3. This is usually done in a vessel at 95°C with 20—30 minutes of vigorous agitation. Caution should be taken to scmb the hydrogen sulfide from the exhaust gas. 

The work-up was done by dropwise addition of ice-cold water (50 mL caution gas evolution ). The reaction mixture was diluted with dichloromethane (lOOmL) and washed with saturated potassium carbonate solution (2 x 50 mL) and brine (2 x 50 mL). The organic layer was dried over magnesium sulfate, filtrated and concentrated using a rotatory evaporator. 

The resultant solid mercury salt is contacted with a mixture of 23 g potassium cyanide (n Caution. Cyanide compounds are extremely poisonous.) and 48 g potassium carbonate in 350 mL of water and 200 mL of heptane. After stirring for several hours, the phases were separated. The heptane phase is stirred vigorously with 12.5 g KCN and 24 g K2C03 in 175 mL water. After separating the phases, the organic phase is washed successively with 250 mL portions of 0.5 M K2C03, HzO, 0.5 M HN03, 0.5 M NaOH, and H20. The solvent is concentrated at reduced pressure to provide 52 g of the title compound. 

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