Question

The is no change in Colour of red litmus and blue litmus pa
Paper when introduced into an aqueous solution of sodium chloride .after passing direct current through the same solution red litmus changes to blue colour .which product is responsible for this change ? Mention any two uses of this
Product

Answer 1

Hi,

◇ In aqueous solution of NaCl all ions exist in the solution in free state , so the hydronium concentration equal the hydroxide concentration so the solution is neutral , no change in litmus indicator

◇ after passing electric current , electric analysis take place ,the chlorine gas evolves at anode, and hydrogen gas evolves at cathode

◇ Hydroxide anion and sodium cation which present at cathode linked together and forming sodium hydroxide NaOH which cause the change in litmus into blue

◇ uses of NaOH preparing washing soda , and saop , purification of petrol from acidic Impurities

Hope the answer is helpful