Chlorinated water

Sulphites are oxidised by chlorine water and solutions con-tainingchloric(I) (hypochlorous)acid or the chlorate(I) (hypochlorite) ion... 

In what way does a solution of hydrogen peroxide react with (a) chlorine water, (b) potassium permanganate solution, (c) potassium dichromate solution, (d) hydrogen sulphide 50 cm of an aqueous solution of hydrogen peroxide were treated with an excess of potassium iodide and dilute sulphuric acid the liberated iodine was titrated with 0.1 M sodium thiosulphate solution and 20.0 cm were required. Calculate the concentration of the hydrogen peroxide solution in g 1" ... 

The presence of chloric(I) acid makes the properties of chlorine water different from those of gaseous chlorine, just as aqueous sulphur dioxide is very different from the gas. Chloric(I) acid is a strong oxidising agent, and in acid solution will even oxidise sulphur to sulphuric acid however, the concentration of free chloric(I) acid in chlorine water is often low and oxidation reactions are not always complete. Nevertheless when chlorine bleaches moist litmus, it is the chloric(I) acid which is formed that produces the bleaching. The reaction of chlorine gas with aqueous bromide or iodide ions which causes displacement of bromine or iodine (see below) may also involve the reaction... 

If chlorine water is boiled the chloricfl) acid decomposes as above, but a little may break down into steam and the acid anhydride, dichlorine monoxide ... 

The smell of chlorine water, somewhat different from that of gaseous chlorine, may be due to minute amounts of evolved dichlorine monoxide ... 

Addition of chlorine water to a bromide solution liberates bromine, which colours the solution brown. 

Chlorine water (acidified NaCIO solution) No action No action Br2 liberated I2 liberated... 

Bromine. Slip the glass cover of a jar momentarily aside, add 2-3 ml. of bromine water, replace the cover and shake the contents of the jar vigorously. Note that the bromine is absorbed only very slowly, in marked contrast to the rapid absorption by ethylene. This slow reaction with bromine water is also in marked contrast to the action of chlorine water, which unites with acetylene with explosive violence. (Therefore do not attempt this test with chlorine or chlorine water.)... 

To determine which halogen is present, take 1-2 ml. of the filtrate from the sodium fusion, and add dilute sulphuric acid until just acid to litmus. Add about 1 ml. of benzene and then about 1 ml. of chlorine water and shake. A yellowish-brown colour in the benzene indicates bromine, and a violet colour iodine. If neither colour appears, the halogen is chlorine. The result may be confirmed by testing the solubility of the silver halide (free from cyanide) in dilute ammonia solution silver chloride is readily soluble, whereas the bromide dissolves with difficulty, and the iodide not at all. 

Chlorine-WATER. Water saturated in the cold with chlorine gas (about 0 7%). 

Chlorine water, saturated solution pass chlorine gas into small amounts of water as needed solutions deteriorate on standing. 

Tetravalent lead is obtained when the metal is subjected to strong oxidizing action, such as in the electrolytic oxidation of lead anodes to lead dioxide, Pb02 when bivalent lead compounds are subjected to powerful oxidizing conditions, as in the calcination of lead monoxide to lead tetroxide, Pb O or by wet oxidation of bivalent lead ions to lead dioxide by chlorine water. The inorganic compounds of tetravalent lead are relatively unstable eg, in the presence of water they hydrolyze to give lead dioxide. 

Removal of Refractory Organics. Ozone reacts slowly or insignificantly with certain micropoUutants in some source waters such as carbon tetrachloride, trichlorethylene (TCE), and perchlorethylene (PCE), as well as in chlorinated waters, ie, ttihalomethanes, THMs (eg, chloroform and bromoform), and haloacetic acids (HAAs) (eg, trichloroacetic acid). Some removal of these compounds occurs in the ozone contactor as a result of volatilization (115). Air-stripping in a packed column is effective for removing some THMs, but not CHBr. THMs can be adsorbed on granular activated carbon (GAG) but the adsorption efficiency is low. 

Properties ndReactions. Phosphoms pentachloride, PCl, is a pale, greenish yellow soHd having a pungent odor (see Table 7). It is made from PCl and chlorine. Water attacks PCl and the violent hydrolysis proceeds in two stages. 

Chlorine Vehicle ndStabilizer. Sulfamic acid reacts with hypochlorous acid to produce /V-ch1orosu1famic acids, compounds in which the chlorine is stiU active but more stable than in hypochlorite form. The commercial interest in this area is for chlorinated water systems in paper mills, ie, for slimicides, cooling towers, and similar appHcations (54) (see INDUSTRIALANTIMICROBIALAGENTS). 

Microstrainers. Microstrainers are rotating steel screens with extremely fine stainless steel mesh (85—170 perforations per square centimeter (13—26/in. )). The flowing Hquid enters the open end of the dmm and passes through the mesh to the effluent end. The mesh traps soHd impurities and rotates with the dmm. A wash-water spray washes the trapped soHds into a hopper for final disposal. The mesh is washed with filtered effluent discharged from jets fitted into the dmm and then exposed to uv radiation to inhibit microbial growth. The mesh is washed with chlorine water at intervals of 7 to 28 days in order to control slime growth removal efficiencies are 30—55% of the appHed BOD and 40—60% of suspended soHds. 

Reaction of hydra2ine with acetone cyanohydrin gives a disubstituted hydra2ine, which upon oxidation with chlorine water gives 2,2 -a2obisisobutyronitrile [78-67-1] (AIBN), a stable, colorless, crystalline material at room temperature. 

Many reagents are able to chlorinate aromatic pyrazole derivatives chlorine-water, chlorine in carbon tetrachloride, hypochlorous acid, chlorine in acetic acid (one of the best experimental procedures), hydrochloric acid and hydrogen peroxide in acetic acid, sulfuryl chloride (another useful procedure), etc. iV-Unsubstituted pyrazoles are often used as silver salts. When methyl groups are present they are sometimes chlorinated yielding CCI3 groups. Formation of dimers and trimers (308 R = C1) has also been observed. 

R/0 unit Reverse Osmosis Unit for water purification in small aquariums and miniature yard-ponds, utilizes a membrane under pressure to filter dissolved solids and pollutants from the water. Two different filter membranes can be used the CTA (cellulose triacetate) membrane is less expensive, but only works with chlorinated water and removes 50-70% of nitrates, and the TFC membrane, which is more expensive, removes 95% of nitrates, but is ruined by chlorine. R/0 wastes water and a system that cleans 100 gallons a day will cost ft-om 400 to 600 with membrane replacement adding to the cost. A unit that handles 140 gallons a day will cost above 700,00. 

This last reaction finds use in volumetric analysis. The use of sulfamic acid to stabilize chlorinated water depends on the equilibrium formation of A-chlorosulfamic acid, which reduces loss of chlorine by evaporation, and slowly re-releases hypochlorous acid by the reverse hydrolysis ... 

Chlor-verbindung,/. chlorine compound, -ver-i fliissigung, /. chlorine liquefaction, -wasser, n. chlorine water. 

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