Calcium nitrate decomposition

By the double decomposition of calcium nitrate and ammonium carbonate (or sulfate) in solution Ca(NO,), + (NH4),CO, - CaCO, + 2NH4NO,... 

The results of the characterization of the product synthesized with Fourier transformation infra-red spectrophotometer (FTIR), X-ray diffractometer (XRD), scanning electron mirror microscope (SEM) and the transmission electron mirror microscope (TEM) illustrate that the product synthesized by the process of double decomposition-precipitation with calcium nitrate and di-ammonium phosphate as the reactants in the SCISR consists of well dispersed particles of about 15 nm in diameter and 50-70 nm long, having a very regular shape and appearance and is confirmed to be hydroxylapatite. 

Calcium nitrate melts below the temperature of onset of the principal decomposition reactions which Doumeng [59] has identified as follows ... 

BARIUM SULFIDE (21109-95-5) BaS Flammable solid. Oxidizes in dry air. Contact with acid, acid fumes, moisture, steam, or moist air causes decomposition with the formation of toxic and flammable hydrogen sulfide gas. Evolved gas can form explosive mixtures with air and may cause spontaneous ignition or explosion. Violent reaction with strong oxidizers, calcium chlorate calcium nitrate chlorine dioxide phosphorus(V) oxide strontium chlorate strontium nitrate. Incompatible with lead dioxide, potassium chlorate, potassium nitrite may explode at elevated temperatures. On small fires, use smothering quantities of dry chemical powder, dry clay, dry groimd limestone (CaCOj), dry soda ash,dry sand or approved Class D extinguishers, do not use water, foam, or hydrous agents. 

This unfavorable effect of low pH is usually intensified by the nitrogen fertilizers themselves, because most of them increase soil acidity. This may be due to the added acid, as in the case of S04 in ammonium sulfate. It may also be due to the NOs added as neutral salts, or to that formed in the nitrification process. If the NOs formed by nitrification is assimilated by plants and converted into protein, there is no appreciable direct effect on soil pH, but if the acid is leached out in the form of nitrate salts then the increase in soil acidity is marked. Even anhydrous ammonia, which is strongly basic, will produce acidity to the extent that it is nitrified and lost to the drainage waters as calcium nitrate or as some other neutral salt. Even if biologically-fixed nitrogen, present in plants as protein, undergoes decomposition to ammonia and oxidation to nitrate, it increases acidity if leaching occurs. Most of the increase in soil acidity is due to the removal of bases as nitrate salts. The possible reactions are explained in detail by Allison (1931). 

In early saltpeter production a nitrous earth was essential. This was the result of the decay of organic and animal matter over a long period. Such decomposition, in the presence of potassium and calcium carbonate, formed potassium and calcium nitrate. According to Agricola [11.6] this slightly fatty earth with an acrid and salty taste , was mixed in a vat with a powder made up of ashes from oak together with unslaked Kme. Water was poured in to fill the vat. The calcium nitrate present in the earth reacted with the potassium carbonate in the oak ash to form potassium nitrate ... 

The nitrate containing 0.1% of ammonium chloride decomposes vigorously below 175°C [1], Presence of 0.1% of calcium chloride or iron(III) chloride in the nitrate lowers its initiation temperature sufficiently to give violent or explosive decomposition. Thermal analysis plots for aluminium chloride, calcium chloride and iron(III) chloride are given [2],... 

Chretien and Woringer [34] described the preparation of silver cyanamide from calcium cyanamide by the action of silver nitrate and also described its explosive properties. Montagu-Pollock [35] described a method for growing large crystals of the salt from its aqueous solution in the presence of ammonium nitrate, ammonia and a surface active agent. Bowden and Montagu-Pollock [36] and Montagu-Pollock [35] studied the slow decomposition of the crystals when heated at temperatures from 150 to 360°C. The course of decomposition was studied by electron microscope. 

The best method of preparation, however, is as follows 2 9 1 grams of aniline in dilute sulphuric acid (1 4) are diazotised at 3° C. with 9 5 grams of sodium nitrite and the solution, made neutral to Congo paper with sodium acetate, is added to a cold aqueous solution of 22 grams of potassium selenocyanate. After fifteen hours steam distillation gives a pale yellow oil, which, when dried over calcium chloride, boils at 134° C. at 10 mm. and at about 250° C. with decomposition at ordinary pressures. The yield is about 50 per cent. When nitrated at -5° C. with nitric acid (density 1 5), p-nitrophenyl selenocyanate and a very small amount of o-nitrophenyl selenocyanate are obtained. p-Chlorophenyl selenocyanate,... 

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