Question

State reason for the following statements: 

(i) Tap water conducts electricity whereas distilled water does not. 

(ii) Dry hydrogen chloride gas does not turn blue litmus red whereas dilute hydrochloric acid does. 

(iii) During summer season, a milk man usually adds a very small amount of baking soda to fresh milk. 

(iv) For a dilution of acid, acid is added into water and not water into acid. 

(v) Ammonia is a base but does not contain hydroxyl group.

Answer 1

(i) Tap water contains ions which conduct electricity, distilled water does not contain ions. 

(ii) Dry HCl does not form ions but HCl gives H⁺ and Cl^– . 

(iii) Baking soda does not allow milk to change to lactic acid which makes milk sour. 

(iv) Adding water to acid is highly exothermic. Therefore water is added to acid very slowly with cooling. 

(v) Ammonia dissolves in water and forms H^– Therefore, it is basic in nature.