PDF chapter test TRY NOW

Viva-voice questions:
Answer variants:
Sodium bicarbonate (NaHCO_3) functions as an antacid, neutralising excess hydrochloric acid (HCl) in our stomach.
Sodium carbonate Na_2CO_3 reacts with hydrochloric acid, carbon dioxide gas CO_2 is liberated.
Because hydrogen gas is heavier than air, it cannot be collected by the downward displacement of air.
 
1. Which gas is liberated when sodium carbonate reacts with hydrochloric acid?
 
2. What is the utility of the reaction between NaHCO_3 and HCl in daily life situation?