What happens when a concentrated solution of sodium chloride (brine) is electrolysed? Write the equation of the reaction involved. (b) Why is the electrolysis of a concentrated solution of sodium chloride known as chlor-alkali process? Name three products of the chlor-alkali process. State two uses of each of these products.

• when a concentrated solution of sodium chloride is electrolysed, it decomposes to form sodium hydroxide, chlorine and hydrogen

→ 2NaCl(aq) + Cl2(g) + H2(g)

2NaCl(aq) + 2HCl(l)

• The electrolysis of a concentrated solution of sodium chloride is known as chlor-alkali because of the products formed, Chlorine and hydrogen.
• Sodium hydroxide, chlorine and hydrogen
• Sodium hydroxide:
  1. Used for making soaps
  2. Manufacturing of paper
• Chlorine
  1. Used in the production of bleaching powder
  2. Used for sterilising drinking water
• Hydrogen
  1. Used as fuels in rockets
  2. Used in hydrogenation of oils