Acids and Oxidizers

Chromic acid use is not recommended if you are doing experiments in conductivity because the chromic ion can coat the walls of the glassware. 

Because chromic acid can be reused, it is often kept in large glass containers. It is important to keep a lid on the container that is (reasonably) air-tight. This containment is not so much for evaporation concerns, but rather because sulfuric acid can absorb 30% of its weight in water, including water from the atmosphere. As it absorbs atmospheric water, its volume changes, and it can overflow the container. 

Disposal. Disposal is best done by reducing the dichromate to the insoluble chromium hydroxide with a sodium thiosulfate solution. The process for neutralizing 100 mL of chromate solution is as follows  

Add sodium carbonate (about 180 g) slowly (while stirring) until the 

Re-acidify this solution with 55 mL of 3 M sulfuric acid (color returns to 

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Glycohc acid also undergoes reduction or hydrogenation with certain metals to form acetic acid, and oxidation by hydrogen peroxide ia the presence of ferrous salts to form glyoxylic acid [298-12A], HCOCOOH, and ia the presence of ferric salts ia neutral solution to form oxaHc acid, HOOCCOOH formic acid, HCOOH and Hberate CO2 and H2O. These reduction and oxidation reactions are not commercially significant. 

Petoxycatboxyhc acids have been obtained from the hydrolysis of stable o2onides with catboxyhc acids, pethydtolysis of acyhinida2ohdes, reaction of ketenes with hydrogen peroxide, electrochemical oxidation of alcohols and catboxyhc acids, and oxidation of catboxyhc acids with oxygen in the presence of o2one (181). 

Chromatographic methods, notably hplc, are available for the simultaneous deterrnination of ascorbic acid as weU as dehydroascorbic acid. Some of these methods result in the separation of ascorbic acid from its isomers, eg, erythorbic acid and oxidation products such as diketogulonic acid. Detection has been by fluorescence, uv absorption, or electrochemical methods (83—85). Polarographic methods have been used because of their accuracy and their ease of operation. Ion exclusion (86) and ion suppression (87) chromatography methods have recently been reported. Other methods for ascorbic acid deterrnination include enzymatic, spectroscopic, paper, thin layer, and gas chromatographic methods. ExceUent reviews of these methods have been pubHshed (73,88,89). 

Zirconium nitride is dissolved by concentrated hydrofluoric acid, dissolved slowly by hot concentrated sulfuric acid, and oxidizes to zirconium oxide above 700°C in air. 

Decahydrate, Pentahydrate, and Anhydrous Borax and Bulk Calcium Borates. The bulk borate products, borax decahydrate and pentahydrate, anhydrous borax, boric acid and oxide, and upgraded colemanite and ulexite, account in both toimage and monetary terms for over 99% of sales of the boron primary products industry (6). Economic considerations for all these products are highly interrelated, and most production and trade statistics do not distinguish the various products. 

Fluorinated Excellent resistance to high temperature, oxidizing acids, and oxidation good resistance to fuels containing up to 30% aromatics... 

Ethylene, a simple, unsaturated organic molecule, is made into translucent, inexpensive, waxy polyethylenes at high pressures. When polyethylenes are applied to substrates, the resulting film is resilient and resistant to acids and oxidizers,... 

Hydroxyetliyl group is transferred to lipoic acid and oxidized to form acetyl dihydro lipoamide... 

The interhalogens have properties intermediate between those of the constituent halogens. Nonmetals form covalent halides metals tend to form ionic halides. The oxoacids of chlorine are all oxidizing agents both acidity and oxidizing strength of oxoacids increase as the oxidation number of the halogen increases. 

In recent years, metallo-chlorophylls and metaUo-chlorophyllins have been considered alternatives to their natural chlorophyll counterparts due to their enhanced color potency, and greater stability against moderate heat, dilute acids, and oxidative agents in general, not to mention their alleged biological activities. 

With few exceptions, by far most applications of tetrazolium salts (e.g., analytical, photographic, and biochemical) utilize their reducibility to the corresponding formazan dyes. Tetrazolium salts, due to their resistance to acid and oxidation and the presence of a positive charge, find use in other applications such as antistatic agents and phase transfer catalysts. Over the past two decades, there have been thousands of citations regarding the applications of tetrazolium salts. Most of these citations are patents with similar or overlapping and even identical claims. Any attempt at completeness would be futile. The applications are sorted where discernible, and the earliest or the broadest claims are cited. 

The Lewis concept permits inclusion of acids and oxidants in a single... 

Figure 1.18 Lewis structures of oxo acids and oxides of phosphorus and sulfur (a) octet rule structures according to Lewis and (b) hypervalent structures.

Jyothi, A. N., Sasikiran, K., Sajeev, M. S., Revamma, R., and Moorthy, S. N. (2005). Gelatinisa-tion properties of cassava starch in the presence of salts, acids, and oxidizing agents. Starch/Starke 57,547-555. 

Quinoline from aniline, glycerol, sulfuric acid and oxidizing agent (e.g. PhN02). 

Nitrosylsulfuric acid hydrolyzes in water forming sulfuric acid and oxides of nitrogen as shown above. 

An acidic solution of tellurium (IV) or tellurium (VI) is treated with sulfur dioxide and hydrazine hydrochloride. Tellurium precipitated from solution can be estimated by gravimetry. Selenium interferes with this test. A volumetric test involves converting tellurium to tellurous acid and oxidizing the acid with excess ceric sulfate in hot sulfuric acid in the presence of Cr3+ ion as catalyst. The excess ceric sulfate is measured by titration with a standard solution of ferrous ammonium sulfate. 

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