mineral acids chlorine is liberated CaOCl + 2HCl CaCl + H O + Cl CaOCl + H SO C aSO + H O + Cl XII XII - - - - . . Manufacture of chlorine: Chlorine is manufactured by the electrolysis of brine in electrolytic process or by oxidation of HCl by air in Deacon’s process. Electrolytic process: When a solution of brine (NaCl) is electrolysed, Na + and Cl - ions are formed.
Na + ion reacts with OH - ions of water and forms sodium hydroxide. Hydrogen and chlorine are liberated as gases. NaCl Na + Cl H O H + OH Na OH NaOH At the cathode, H + e H H + H H At the anode, Cl Cl + e Cl + Cl Cl Deacon’s process: In this process a mixture of air and hydrochloric acid is passed up a chamber containing a number of shelves, pumice stones soaked in cuprous chloride are placed. Hot gases at about K are passed through a jacket that surrounds the chamber.
→ ↑ 4HCl + O 2H O + 2Cl C Cu Cl The chlorine obtained by this method is dilute and is employed for the manufacture of bleaching powder. The catalysed reaction is given below, 2Cu Cl + O 2Cu OCl Cu OCl + 2HCl Cuprous oxy chloride Cupric chloride Cuprous chl 2CuCl + H O 2CuCl Cu Cl oride + Cl Physical properties: Chlorine is a greenish yellow gas with a pungent irritating odour. It produces headache when inhaled even in small quantities whereas inhalation of large quantities could be fatal. It is .
times heavier than air. Chlorine is soluble in water and its solution is referred as chlorine water. It deposits greenish yellow crystals of chlorine hydrate (Cl .8H O). It can be converted into liquid (Boiling point – .
° C) and yellow crystalline solid (Melting point - ° C) Chemical properties: Action with metals and non-metals: It reacts with metals and non metals to give the corresponding chlorides. 2Na + Cl 2NaCl 2Fe +