Which gas is liberated when dilute hydrochloric acid reacts with sodium carbonate? How will you test for the presence of this gas?
When dilute hydrochloric acid reacts with sodium hydrogen carbonate, Carbon dioxide gas is liberated.

We recognize the presence of carbon dioxide by passing it through lime water which turns milky or a white precipitate of calcium carbonate is formed. If excessive carbon dioxide is passed through the milkylime water, the solution becomes clear after sometime.


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