Carbon dioxide over ammonia solutions

The analytical phase generally involves the use of very dilute solutions and a relatively high ratio of oxidant to substrate. Solutions of a concentration of 0.01 M to 0.001 M (in periodate ion) should be employed in an excess of two to three hundred percent (of oxidant) over the expected consumption, in order to elicit a valid value for the selective oxidation. This value can best be determined by timed measurements of the oxidant consumption, followed by the construction of a rate curve as previously described. If extensive overoxidation occurs, measures should be taken to minimize it, in order that the break in the curve may be recognized, and, thence, the true consumption of oxidant. After the reaction has, as far as possible, been brought under control, the analytical determination of certain simple reaction-products (such as total acid, formaldehyde, carbon dioxide, and ammonia) often aids in revealing what the reacting structures actually were. When possible, these values should be determined at timed intervals and be plotted as a rate curve. A very useful tool in this type of investigation, particularly when applied to carbohydrates, has been the polarimeter. With such preliminary information at hand, a structure can often be proposed, or the best conditions for a synthetic operation can be outlined. 

Data for the three-component system ammonia-water-carbon dioxide are in a less satisfactory state. Pexton and Badger 22) report data at 20°, 30°, and 40° C. Badger and Wilson 1) extend the data to the higher temperature range of 90° to 100° C., but this was done with solutions not at the boil. Egalon, Vanhille, and Wille-myns (5) measured the partial pressures of ammonia and carbon dioxide over solutions of ammonium carbonates in the 20° to 50° C. range. 

Summary Ammonium perchlorate is prepared by adding an ammonia solution to a concentrated solution of sodium perchlorate, and then passing carbon dioxide into the solution over several hours to precipitate the sodium as the water insoluble sodium bicarbonate. The ammonium perchlorate remains in solution, and the solution is then filtered to remove the water insoluble sodium bicarbonate. Thereafter, the ammonium perchlorate is then collected by recrystallization in the usual means. 

Ion-selective electrodes can be used for analytical determinations over an extremely wide range of solution concentrations (from 10" to 10 M to saturation) and are therefore applicable to trace as well as to major-constituent analysis. There are presently about two dozen ion-selective electrodes commercially available for cations, including the heavy metals for anions such as fluoride, sulfide, and the halides and for gases such as oxygen, carbon dioxide, and ammonia. ... 

In one patent (31), a filtered, heated mixture of air, methane, and ammonia ia a volume ratio of 5 1 1 was passed over a 90% platinum—10% rhodium gauze catalyst at 200 kPa (2 atm). The unreacted ammonia was absorbed from the off-gas ia a phosphate solution that was subsequently stripped and refined to 90% ammonia—10% water and recycled to the converter. The yield of hydrogen cyanide from ammonia was about 80%. On the basis of these data, the converter off-gas mol % composition can be estimated nitrogen, 49.9% water, 21.7% hydrogen, 13.5% hydrogen cyanide, 8.1% carbon monoxide, 3.7% carbon dioxide, 0.2% methane, 0.6% and ammonia, 2.3%. 

Weak acids with weak bases. The titration of a weak acid and a weak base can be readily carried out, and frequently it is preferable to employ this procedure rather than use a strong base. Curve (c) in Fig. 13.2 is the titration curve of 0.003 M acetic acid with 0.0973 M aqueous ammonia solution. The neutralisation curve up to the equivalence point is similar to that obtained with sodium hydroxide solution, since both sodium and ammonium acetates are strong electrolytes after the equivalence point an excess of aqueous ammonia solution has little effect upon the conductance, as its dissociation is depressed by the ammonium salt present in the solution. The advantages over the use of strong alkali are that the end point is easier to detect, and in dilute solution the influence of carbon dioxide may be neglected. 

Experiment 3. Rates of Formation of Ethylenediamine and Ammonia vs. Rate of Disappearance of Cobalt (II). Carbon dioxide-free air was bubbled through the solution. Ammonia, ethylenediamine, and cobalt (II) were determined periodically over a total reaction time of 5 hours. The results of this experiment are collected in Table I and plotted in Figure 3. The ammonia measured was actually the ammonia volatilized during the reaction, but it was calculated as moles per liter of solution in order to be consistent with the ethylenediamine and cobalt (II) results. 

Fig. 81. Fill two-neck bottle 1 up to one-fourth of its volume with a granulated alkali (IV/ten working with an alkali, wear eye protection Handle the alkali only with pincers ) Pour a concentrated ammonia solution into dropping funnel 2. Pour vaseline or paraffin oil (a bubble counter) into wash bottle 3. Put a granulated alkali into drying column 4. What substances should be used for drying ammonia Fasten a dry bottle over gas-discharge tube 6. When you have assembled the apparatus, put solid carbon dioxide ( dry ice ) into...

An autoclave (7) is supplied with an aqueous solution that contains 600 g of ammonium nitrate and 40 g of ammonia per litre. Calcium cyanamide in the ratio of 500 g CaCN2 to every litre of solution is then added from container (2) after being weighed at (3). The autoclave is closed, carbon dioxide is introduced, while the contents are cooled with water so that the temperature does not exceed 100°C. When no more carbon dioxide is absorbed, the supply is stopped, and so is the inflow of cooling water. The reaction mixture is now steam heated to 160°C. Afterwards a communicating valve joining the autoclave (7) with a second autoclave (75) is opened. The other vessel (75) is filled with ammonium nitrate solution prepared for the next charge. In this way the major part of the ammonia passes from autoclave (7) over to autoclave (75). After the reaction is finished the mixture is raised from the auto-... 

The Ammonia-Soda or Solvay Process.—In this process sodium bicarbonate is produced by the action of carbon dioxide on an ammoniacal solution of common salt. The bicarbonate crystallises out, leaving ammonium chloride in solution, the ammonia being recovered by heating the solution with lime, and used over again. The lime employed is burnt at the works, the lime-kiln gas being the source of some of the carbon dioxide, while the gas expelled from the bicarbonate by calcination to make normal carbonate provides the remainder. The salt solution... 

---