State the chemical properties on which the following uses of baking soda are based.
(i) as an antacid
(ii) as soda-acid fire extinguisher
(iii) To make bread and cake soft and spongy

State the chemical property in each case on which the following uses of baking soda are based : (i) as an antacid. (ii) as a constituent of baking powder.

(a) A student dropped a few pieces of marble in dilute hydrochloric acid contained in a test tube. The evolved gas was passed through lime water. What changes would be observed in lime water ? Write balanced chemical equations for both the changes observed. (b) State the chemical property in each case on which the following uses of baking soda are based: (i) as an antacid (ii) as a constituent of baking powder.