Question

A student is studying the properties of acetic acid. List two physical properties of acetic acid he observes. What happens when he adds a pinch of sodium hydrogen carbonate to this acid? Write any two observations.

Answer 1

Physical properties of acetic acid:
a) It freezes during winters, as its melting point is 290 K.
b) It has a characteristic vinegar-like odour.

When a pinch of sodium hydrogen carbonate is added to acetic acid in a test tube, a brisk effervescence is observed due to evolution of a colourless and odourless carbon dioxide gas, CO₂. 
Chemical equations for the reaction:
CH₃COOH(aq) + NaHCO₃(s) → CH₃COONa(aq) + H₂O(l) + CO₂(g)