Hydrogen combination with chlorine

Chlorine combines with hydrogen forming hydrogen chloride, HCl. The reaction occurs rapidly when exposed to hght, involving a photochemical chain initiation step. 

The chlorine value can be converted into hypochlorite bleach by absorption into lime or caustic soda. It can also be used to produce hydrogen chloride by combining with hydrogen in a burner. The latter technique is particularly useful when the acid can be consumed on site in brine acidification or ion-exchange resin regeneration. Another approach that has found some favour in the past is the absorption of the chlorine into a solvent from which it could then be stripped and returned to the liquefaction plant. 

Chlorine combines with numerous other elements as well. Hydrogen and chlorine gases are extremely explosive when mixed, and they produce hydrogen chloride (HCl) that, when dissolved in water, results in hydrochloric acid Hj + Cl 2HC1. 

The stoichiometric equivalents of halogen fluorides, i.e. chlorine monofluoride, bromine monofluoride and iodine monofluoride, have found a wide application in addition reactions to double bonds. The equivalents are obtained by reacting A -haloamides or free halogens in combination with hydrogen fluoride or its salts as the source of fluoride ions. The reactions proceed under mild conditions at — 80 to 20 "C in anhydrous hydrofluoric acid or diethyl ether, tetrahydro-furan, dichloromethane or chloroform mainly by electrophilic addition with Markovnikov-type regioselectivity (anti addition).26-28... 

Chlorine combines with the gas when the mixture is exposed to sunlight or when the sulphur dioxide is employed in solution in acetic acid or in camphor, the product being sulphuryl chloride 3 no combination occurs in the dark in the absence of a catalyst. In the presence of water the products are sulphuric acid and hydrochloric acid.4 Bromine does not combine in this manner, nor does hydrogen chloride, the freezing-point curve of the latter with sulphur dioxide showing only the formation of a eutectic mixture.5... 

LOWER A BURNING CANDLE INTO A BOTTLE OF CHLORINE GAS. A DENSE SMOKE OF CARBON IS FORMED. THE CHLORINE COMBINES WITH THE HYDROGEN OF THE CANDLE AND SETS THE CARBON IN IT FREE AS SOOT. 

Compounds 1-3 were briefly reported as precursors to titanium thin films. 16 26 28 The thermoanalytical studies conducted on these molecules gave contradictory results to those reported in the literature. We found that these molecules do decompose, but form non-volatile products in the precursor vessel.29 Consequently, the formation of CVD films seems to be more difficult than previously reported. Compounds 4 and 5 contain large amounts of chlorine atoms that can participate in the formation of the film or combine with hydrogen atoms so as to corrode the steel substrates. However, these compounds are relatively volatile,29 and 5 has been successfully used for CVD of titanium carbide.26,30-33 In order to maintain sufficient volatility but reduce the Cl content of the molecule, we have studied compound 6 which contains just one Cl atom. The TG behavior of 6 remains similar to that of 5. The TG curve of Figure 15.3 shows a high volatility of this compound between 523 K and 573 K, and its decomposition below 623 K. Compound 6 can therefore be considered as a good candidate precursor to titanium carbide thin films.29... 

It is known that the atoms of different elements poeseos diffiBisfit powers of combining with and of replacing atoms of hydrogen. Thus One atom of chlorine combines with one atom of hydrogen,... 

But the valence of the elements is not fixed and invariable. Thus, while chlorin and iodin each combine with hydrogen, atom for atom, and in those compounds are consequently univalent, they unite with each other to form two compounds—one containing one atom of iodin and one of chlorin, the other containing one atom of iodin and three of chlorin. Chlorin being univalent, iodin is obviously trivalent in the second of these compounds. Again, phosphorus forms two chlorids, one containing three, the other five atoms of chlorin to one of phosphorus. 

In the chlor-alkali industry, brine (mixture of sodium chloride and water) solution is electrolyzed producing chlorine (CI2), sodium hydroxide, and hydrogen (H2). The pure chlorine gas can be combined with hydrogen to produce hydrogen chloride. 

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