Answer. When acids react with carbonates and bicarbonates, they form salts and carbon dioxide gas evolves out. For example, reaction of Calcium carbonate with hydrochloric acid forms calcium chloride and carbon dioxide evolves out.
CaCO3(aq) + 2HCl(aq) CaCl2(aq) + CO2(g) + H2O(1)
Similarly, when sulphuric acid reacts with sodium bicarbonate, sodium sulphate forms along with evolution of carbondioxcide gas.
2NaHCO3 (aq) + H2SO4 (aq) Na2SO4(aq) + 2CO(aq) + 2H2O(1)