Question

during the prepration of NaOH by chloro-alkalai process,name the gases evolved at anode and cathode.why is this process called chloro-alkalai process

Answer 1

during the preparation of NaOH by chloro alkalai process the gases which is liberated from cathode is hydrogen gas and the gas which is liberated from anode is chlorine gas.
The chloralkali process (also chlor-alkali and chlor alkali) is an industrial process for the electrolysis of sodium chloride. It is the technology used to produce chlorine andsodium hydroxide (lye/caustic soda),[1] which are commodity chemicals required by industry. 35 million tons of chlorine were prepared by this process in 1987.[2]Industrial scale production began in 1892.

Usually the process is conducted on a brine (an aqueous solution of NaCl), in which case NaOH, hydrogen, and chlorine result. When using calcium chloride or potassium chloride, the products contain calcium or potassium instead of sodium. Related processes are known that use molten NaCl to give chlorine and sodium metal or condensed hydrogen chloride to give hydrogen and chlorine.

The process has a high energy consumption, for example over 4 billion kWh per year in West Germany in 1985.[3] Because the process gives equivalent amounts of chlorine and sodium hydroxide (two moles of sodium hydroxide per mole of chlorine), it is necessary to find a use for these products in the same proportion. For every mole of chlorine produced, one mole of hydrogen is produced. Much of this hydrogen is used to produce hydrochloric acid or ammonia, or is used in the hydrogenation of organic compounds.[4]
The chloralkali process (also chlor-alkali and chlor alkali) is an industrial process for the electrolysis of sodium chloride. It is the technology used to produce chlorine andsodium hydroxide (lye/caustic soda),[1] which are commodity chemicals required by industry. 35 million tons of chlorine were prepared by this process in 1987.[2]Industrial scale production began in 1892.

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