Question

while performing the experiment to study the properties of HCl and Na2Co3, how can student confirm whether hydrogen or carbon dioxide is liberated

Answer 1

if hydrogen gas is liberated then it will formed in bubble and u can know by bringing a burning candle near to it . it will burst with pop sound .
and carbon dioxide can be predicted by passing lime water through it .lime water become milky .

Answer 2

HYDROGEN cam b distinguished when u bring a burning candle to it...
CO2 can be distinguished when lime water is passed through it...it would turn milky...

hope it helps