Benzoic acid gives a brisk effervescene with saturated `NaHCO_(3)` solution but benzaldehyde fails to respond to this test.
`underset("Benzoic acid")underset()(C_(6)H_(5)COOH)+NaHCO_(3)rarrunderset("Sod. benzoate")underset()(C_(6)H_(5)COONa)+H_(2)O+underset("effervesence")underset("Brisk")underset()(CO_(2))`
