A dilute solution of sodium carbonate was added to two test tubes – one containing dil HCl (A) and the other containing dilute NaOH (B). The correct observation was
A brown coloured gas librated in test tube A.
A brown coloured gas liberated in test tube B.
A colourless gas liberated in test tube A.
A colourless gas liberated in test tube B.
A colourless gas liberated in test tube A.