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For preparation of which of the following compounds is the chlor-alkali process used?
Sodium hydroxide (NaOH)
Calcium chloride (CaCl2тАЛ)
Sodium carbonate (Na2тАЛCO3тАЛ)
Bleaching powder (CaOCl2тАЛ)
Sodium hydroxide (NaOH)
The chlor-alkali process is an industrial electrolysis method used for the production of sodium hydroxide (caustic soda), chlorine gas, and hydrogen gas from an aqueous solution of sodium chloride (brine). The term 'chlor' refers to chlorine and 'alkali' refers to sodium hydroxide.
The chlor-alkali process is an industrial electrolysis method used for the production of sodium hydroxide (caustic soda), chlorine gas, and hydrogen gas from an aqueous solution of sodium chloride (brine). The term 'chlor' refers to chlorine and 'alkali' refers to sodium hydroxide.
Think of it like an electrolysis factory where table salt dissolved in water is zapped with electricity, acting like a chemical sorting machine that separates the mixture into useful industrial products: bleach components (chlorine) and soap components (sodium hydroxide).
Remember 'CHLOR-ALKALI' as: Chlorine from Anode, Alkali (NaOH) from Cathode!
2NaCl(aq)тАЛ+2H2тАЛO(l)тАЛElectricityтАЛ2NaOH(aq)тАЛ+Cl2(g)тАЛ+H2(g)тАЛ тАФ Overall Chlor-Alkali reaction
2ClтИТтЖТCl2(g)тАЛ+2eтИТ тАФ Oxidation at Anode
2H2тАЛO+2eтИТтЖТH2(g)тАЛ+2OHтИТ тАФ Reduction at Cathode
When electricity is passed through an aqueous solution of sodium chloride (known as brine, NaCl), it decomposes to form sodium hydroxide, chlorine gas, and hydrogen gas. At the anode, chloride ions are oxidized to release chlorine gas (2ClтИТтЖТCl2тАЛ+2eтИТ), while at the cathode, water molecules are reduced to produce hydrogen gas and hydroxide ions (2H2тАЛO+2eтИТтЖТH2тАЛ+2OHтИТ). Sodium ions (Na+) combine with hydroxide ions (OHтИТ) in the solution to form sodium hydroxide (NaOH).
Brine is an aqueous solution of sodium chloride (NaCl).
Chlorine gas is released at the anode (+) electrode.
Hydrogen gas is released at the cathode (-) electrode.
Sodium hydroxide (NaOH) solution remains near the cathode.
Produces three highly valuable industrial chemicals simultaneously from cheap raw materials (salt and water).
Consumes a large amount of electrical energy during electrolysis.
Chlorine is used for water treatment, manufacturing PVC, disinfectants, and CFCs.
Sodium hydroxide (caustic soda) is used for degreasing metals, soap making, paper making, and detergents.
Hydrogen is used in fuels, margarine manufacturing, and ammonia synthesis.
Option B (NaHCO3тАЛ) is prepared using the Solvay process.
Option C (Na2тАЛCO3тАЛ) is also produced via the Solvay process.
Option D (NaCl) is the raw starting material (brine) used in the chlor-alkali process.
A is correct тАФ The chlor-alkali process is used for the preparation of sodium hydroxide (alkali) along with chlorine gas and hydrogen gas.
Always remember that the electrolysis of aqueous sodium chloride produces NaOH, Cl2, and H2, whereas molten NaCl electrolysis produces sodium metal and chlorine gas.