Question

Give suitable reason for the following statements:
(i) We feel burning sensation in the stomach when we overeat.
(ii) The crystals of washing soda change to white powder on exposure to air.
(iii) An aqueous solution of sodium chloride is neutral but an aqueous solution of sodium carbonate is basic.

Answer 1

(i) When we overeat excess of acid is produced in the stomach which causes burning sensation.
(ii) Washing soda is sodium carbonate decahyclrate which when exposed to air loses 10 molecules of water and changes to white powder.
(iii) Sodium chloride is a salt of strong acid HCI and strong base NaOH, so it is neutral.
Sodium carbonate is a salt of weak acid H2CO3 and strong base NaOH, so it is basic.