Decanting Solutions

One major disadvantage of decantation is that some liquid will remain in the flask this problem may be minimized by using a Pasteur pipet to transfer the last few milliliters and rinsing the residue with several milliliters of pure solvent that 

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A copious white crystalline precipitate soon settles from the anode to the bottom of the tube T. After an hour or so, interrupt the process, decant the electrolyte from the crystals, collect them on a small filter in a Gooch crucible, wash them with alcohol using a pump, and dry them in air. The decanted solution may be used for another run. 

To obtain it perfectly free from alumina, Schubert directs hydrate of potassa to be prepared by decomposing the sulphate of that base by means of hydrate of baryta. A solution of this latter salt is added to one of pure sulphate of potassa in exactly sufficient quantity to effect decomposition. Tho decanted solution is then evaporated as previously described. 

The proteinoid microspheres (Fig. 1), as simulated protocells, form from virtually all of the known wide variety of thermal copolyamino acids 2). Microspheres are formed if the aqueous or aqueous salt solution of proteinoid is heated and the clear decanted solution is allowed to cool. This self-assembly may also be effected by chilling solutions saturated at room temperature. Sonication at room temperature can be used. 

Wear nitrile rubber gloves, eye protection, laboratory coat, and self-contained breathing apparatus if necessary. Cover spill with a 1 1 1 mixture by weight of sodium carbonate or calcium carbonate, clay cat litter (bentonite), and sand. Scoop into a container and transport to the fume hood. Add to a pail of water. Cautiously, and while stirring, add to an alkaline solution of calcium hypochlorite or household bleach. After 24 hours, decant solution to the drain with 50 times its volume of water. Discard the solid residue with normal refuse.4,5... 

Expt no. Reactants Undissolved Dissolved Ptp4 (XeF2)j.PtF4 from decanted solution Combined XeFj mmol Xep2... 

In a 3-I. beaker are placed 750 cc. of 95 per cent ethyl alcohol and 1.5 g. of finely ground copper sulfate, and the mixture is heated on a hot plate or steam bath to 70°. Ihe diazonium slurry is added in about 30-cc. portions to the well-stirred alcohol the temperature is kept between 60° and 70°, and the nitrogen evolution is allowed to subside considerably between additions. The final traces of diazonium slurry are washed into the alcohol with small amounts of the decanted solution, the remainder of which is then added to the alcohol in loo-cc. portions. The reaction mixture is heated and stirred at 65-70° for half an hour, and then cooled without agitation to 5°. The ffi-iodobenzoic acid which separates is filtered with suction on a Buchner funnel, washed with three 50-cc. portions of cold water, and dried at 90-110°. There is obtained 107-116 g. of crude, brown w-iodobenzoic acid (86-93 per cent of the theoretical amount) (Note r). 

To a clear solution of the tricarbonatocobaltate(III) ion (made from 14.5 g of Co(N03)2-6H20) is added 4.1 mL (0.05 mole) of 98% 1,2-ethanediamine. The mixture is stirred at room temperature for a few minutes, whereupon the color of the solution becomes blue. The solution is cooled rapidly with ice, 50 mL of ethanol is added, and the whole is allowed to stand in an ice-salt bath for a while. An aqueous layer forms and is decanted, and 50 mL of ethanol is added to the residual blue oil. This procedure is repeated until the decanted solution becomes clear. To the final oily material is added 50 mL of ethanol, and the whole is allowed to stand in. an ice-salt bath for 30 minutes to crystallize the... 

Batch leach experiments were performed on tailings material to determine the nature of contaminants distributed on sand and silt and clay-sized fractions. For the batch leach experiments, a mixture of tailings material was prepared using a chemical dispersant (sodium hexametaphosphate (NaPO ) ). The mixture was shaken and allowed to settle in covered beakers for sufficient time such that no particles with a diameter > 50 /im remained in suspension. The fines, which remained in suspension, represented the silt and clay-sized fraction of the samples. At the end of the settling period, the liquid was decanted from the beaker. The remaining sand-sized tailings were dried and transferred to a sealed vial. The decanted solution was passed through a 0.45 /im membrane filter, previously washed with distilled water, and the filtrate was collected and placed in a sealed container. The solids were dried and transferred to a sealed vial. The samples were then analyzed by instrumental neutron activation analysis. 

Decant solution and wash the pellet with 70% EtOH. Centrifuge at 4°C, 10,000 rpm for 10 min and decant. Dry oligonucleotide pellet. 

After four charges, the settled precipitate of zinc sulfide, Terrana, etc., is diluted with water, settled again, and the decanted solution used for dissolving the next charge. The residues are discarded. 

Soaps are colored by adding to them small amounts of copperas, ultra-marine, or other pigment. Transparent soaps are made by dissolving a common soap in alcohol and distilling off the latter from the decanted solution until the residue is obtained as a clear transparent jelly, which is finally carefully dried in moulds. The addition of glycerol and alcohol or a solution of cane sugar to cold-process soaps, renders them more or less transparent. 

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