Question

On adding NaHCO3 to acetic acid, one immediately a) observes strong effervescence b) hears a hissing sound c) gets pungent smell d) observes the evolution of a coloured gas

Answer 1

The gas evolved will be carbon dioxide.

NaHCO3 + CH3COOH ==>CH3COONa + H2O + CO2

Answer 2

Brisk effervescenceis created by the CO2 gas which is liberated in the above reaction