Calces acidic

EJAcidity. Dissolve a 100 g sample in 400 ml of distd w, filter and titrate the filtrate with N/lONaOH soln using methyl red indicator. Run a blank detn on the same amt of distd w and methyl red. Calc acidity as %-age of nitric acid (Ref 8, p 4)... 

Guyton s two-fluid theory of calcination came remarkably close to Lavoisier s oxygen theory. According to Guyton s hypothesis, acids had to contain fixed air, since they furnished it to metallic earths to produce metallic calces. Acids did not touch metallic calces because both were neutralized by the same principle fixed air. Metallic earths were, therefore, always united to phlogiston, fixed air, or acids. All these facts showed that... 

Calcium Oxide (lime, Quicklime, Burnt Lime, Calx, Unslaked Lime, Fluxing Lime). CaO, mw 56.08, white or greyish-white lumps or powd, mp 2580°, bp 2850°, d 3.25-3.40g/cc. SI sol in w with formation of calcium hydroxide and evolution of large amts of heat sol in acids, and insol in ethanol. Coml prepn consists of heating calcium carbonate in kilns at 1000—1100° until all of the C02 is driven off. Lab prepn is by burning calcium carbonate or calcium oxalate at about 800° using a quartz crucible in an electric furnace... 

This I also say, that if the spirit of common salt be joined to the spirit of wine, and distilled together with it, it becomes sweet, and loses its acidity. This prepared spirit does not dissolve gold bodily, but if it be poured on prepared calx of gold, it extracts the essence of its colour and redness. If this be rightly done, it reduces the white and pure moon to the colour of that body from which it was itself extracted. The old body may also receive back its former colour through the love of alluring Venus, from whose blood it, in the first instance, derived its origin. 

The reddish brown calx dissolved in sulfuric acid to give a yellow solution which became purple when reduced with zinc, tin, or iron, and when the pulverized mineral was fused with powdered charcoal, a purple slag was formed. 

Mercury, for example, could be dissolved in acid or converted to a calx, and from either the mercury could be obtained again in metallic form. It could be combined with mineral sulphur to make cinnabar (mercuric sulfide), a more convenient form for transportation than the heavy liquid metal. To get the metallic mercury back, the artificial cinnabar was heated with lime thirteen and half ounces of mercury can be obtained from a pound of artificial cinnabar. Lemery speaks of the cause of this disguise of Mercury in Cinnabar... 

Similarly, Lavoisier had no explanation for the origin of the inflammable air obtained when metals were dissolved in acids. In the phlogistic view metals contained phlogiston combined with the metallic calx. When the metal was dissolved in acid, the calx combined with the acid to form the neutral salt and the phlogiston was liberated as inflammable air. For Lavoisier, the metal and the water were considered elemental and the acid consisted only of oxygen combined with a simple acidifiable basis. There was no possible source for the inflammable air produced. As a further puzzle, inflammable air when burned ought to produce an acid, but earlier experiments had failed to confirm that hypothesis. As the gas had always been burned in the presence of water, the actual production of more water was overlooked. 

June of 1783. He immediately repeated the experiments with special attention to the quantitative production of the water. After a systematic investigation he concluded that the solution of metals in acids was just as much an oxidation process as their calcination in air, that the metals had to combine with oxygen to form the calx before they could dissolve in acids. The oxygen required was provided either by the acid, in which case the reduced acid gas was liberated (SO2 or NO) or by the water, in which case the gaseous product was inflammable air (hydrogen). The resulting metallic calx then combined with additional acid to form the neutral salt. 

There are other less familiar chemical behaviors that the phlogistic view readily described. Near the middle of the century Macquer discovered that if white arsenic (AS2O3) was treated with nitric acid a new acid was formed which contained arsenic as its basis. Later phlogistonists explained this by extending the traditional relationship between a metal and its calx, In this case, the metallic arsenic by losing some of its phlogiston would form the... 

Aspaitase ill immobilized R. calx cells catalyzes, L-aspartic acid production from fimrarate and ammonia. 

These transformations of metals and their ores or calxes were not all that Stahl s notion of principles explained. The combustion of sulfur yielded an acid, which Stahl, following Becher, called the universal acid, because he considered it to be the principle of acidity, the material constituent that was essential to the formation of every acid. Since sulfur could burn, it must contain phlogiston. Today, we consider sulfur, like the metals, to be a chemical element. For Stahl, the universal acid was a mixt. So were sulfur and the metals, because he believed that they contained more than one material constituent. That is, they were more complex than the products of their combustion. 

The action of acid on the metal, or rather on the metallic calx. ... 

---