Hydrochloric acid chlorine from

Transfer 25 ml. of this dilute solution by means of a pipette to a conical flask, and add similarly 50 ml. of Ml 10 iodine solution. Now-add 10% sodium hydroxide solution until the liquid becomes pale yeilow in colour, and allow the solution to stand, with occasional shaking, at room temperature for at least 10 minutes. Then acidify with dilute hydrochloric acid (free from chlorine) in order to liberate the remaining iodine. Titrate the latter w ith Mho sodium thiosulphate solution, using starch as an indicator in the usual way. 

The raw precious metal concentrate is totally dissolved in hydrochloric acid—chlorine solution to form the soluble chloride ions of each of the metals. Silver remains as insoluble silver chloride and can be filtered off. Gold, in the form of [AuClJ, is extracted with, eg, tributyl phosphite or methyl isobutyl ketone. Base metals are also extracted in this step, and are removed from the organic phase by scmbbing with dilute hydrochloric acid (HCl). Iron powder is then used to reduce the gold species and recover them from the organic phase. 

Seaetione.—1. By the action of hydrochloric acid, chlorine is evolved from both the hydrochloric acid and hypocblorous acid ... 

By adding hydrochloric acid dropwise from funnel 2, obtain a uniform stream of chlorine. After 2-3 ml of liquid chlorine gather in the receiver, disconnect the apparatus from wash bottle 4. Pour the obtained liquid chlorine into five bottles and cover them with glass plates. 

Preparation of Nj5 Bromate Solution.—5-567 gms. (1/30 mol.) of potassium bromate are dissolved in water to 1,000 c.cs. 25 c.cs. are withdrawn, diluted to 200 c.cs. with water, 3—5 gms. of potassium bromide (free from bromate), 3—5 gms. potassium iodide (free from iodate) and 5 c.cs. cone, hydrochloric acid (free from chlorine or iron) added. The liberated iodine is titrated with thiosulphate in the usual way, and the bromine equivalent of the bromate solution thus obtained. 

Where chain reactions have been studied they are found to be the same whether started by X-rays or by ordinary light. Gunther19 measured the amount of hydrochloric acid formed from hydrogen and chlorine under the influence of X-rays, and then in the same reaction chamber he determined the amount of reaction produced by a measured quantity of visible light. The latter measurements determined the length of the chemical chain and from the total chemical reaction he was able to calculate the number of chains started by the X-rays. Combining these data with experiments on ionization, he concluded that each ion produced by X-rays starts a chain, just as does each photon of visible light, or each ion produced by alpha particles. 

Another method for generating chlorine dioxide involves the acidification of sodium chlorite with hydrochloric acid to from chlorine dioxide, sodium chloride, and water ... 

Silicic acid gel, when evaporated with a slight excess of 30 per cent, peroxide, yields a highly active amorphous residue which continuously evolves ozonised oxygen. It liberates chlorine from hydrochloric acid, iodine from potassium iodide, decolorises permanganate, and evolves ozone with concentrated sulphuric acid.4 Possibly a persilicic acid is formed. Thiosulphates are at first oxidised to tetrathionates, the solution becoming alkaline 5... 

Munich An integrated process for making chlorine dioxide from hydrochloric acid. Sodium chlorate is made electrochemically from sodium chloride, and this is reduced with hydrochloric acid. Developed from the Kesting process by H. Frohler and E. Rossberger at the Elektrochemische Werke Munchen, Germany, and first commercialized in 1974. The essential improvement over the Resting process is the use of titanium electrodes coated with ruthenium oxide for the electrolytic... 

Barium perferrate is the most stable salt of the series. It is insoluble in water, and its suspension in water may be boiled without decomposition. It is practically unaffected by dilute sulphuric acid in the cold. Apart from this it is readily attacked by acids, even carbonic dilute hydrochloric or nitric acid decomposes it instantly, yielding salts of barium and iron.5 When treated m the cold with very dilute hydrochloric acid, chlorine is evolved and the solution assumes a red colour, probably due to the presence of the Fe04" ion.G Acetic acid reacts similarly. On boiling, the solution evolves oxygen, and becomes colourless. 

Chlorine and Alkali from Sodium Chloride, Chlorine from Hydrochloric Acid, Chlorine-Oxygen Compounds [1-7]... 

Hydrochloric acid Synthesis from hydrogna and chlorine Water... 

Hydiiodic add gas is transparent, colourless, acid to the taste, and suffocating to the smell. It has a Sp. G. of 4 385, fumes strongly in the air, and is absorbed by water to ets great an extent as hydrochloric acid gas, from which it is not to be easily distinguished, except by the action of chlorine or bromine, which seizing the hydrogen, disengage the purple vapours of iodine. 

A measure of the degree of contamination is given by the content of halogen compounds that can be adsorbed from the acid by activated carbon (AOX content). In nearly all chlorination reactions the chlorine is incompletely consumed, so that a fluctuating proportion of free chlorine usually occurs Iwth in tfie hydrochloric acid recovered from the residual gases from the chlorination process and in the waste gases. 

Disadvantages of the pure CR resulting from the high chlorine content include low temperature resistance (60 °C wet, 90 °C dry) on account of elimination of hydrochloric acid. Chlorinated rubber also tends to undergo yellowing where exposed to atmospheric influences. 

PVC-Blends extinguishes immediately after removal from flame green flame border stinging odor of hydrochloric acid Chlorine... 

Deacon published a theory of the chlorine process. The important method for purifying the hydrochloric acid gas from the saltcake furnaces was devised by Robert Hasenclever. Deacon s process came into general use only after his death, since the Weldon process was simpler and gave a more concentrated (85-90 per cent) gas. Deacon in 1872 warned Mond of the possibilities of the ammonia-soda process. He amassed a considerable fortune of over 3 100,000. Another chlorine process invented by Dunlop (1849), involving the oxidation of hydrochloric acid by nitric acid, has recently been revived. 

Products reported from the combustion of dieldrin at 900°C include carbon monoxide, carbon dioxide, hydrochloric acid, chlorine and unidenhfied compounds (Kennedy et al., 1972a). When dieldrin is heated to decomposition (>175°C), very toxic chloride fumes are emitted (Lewis, 1990). 

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