(i) Fehling’s solution test: Aliphatic aldehydes reduce Fehling’s solution but aromatic aldehydes do not. Thus, acetaldehyde gives a red ppt. of Cu2O with Fehling’s solution but benzaldehyde does not.
(ii) Iodoform test: Acetaldehyde reacts with NaOI (I2/NaOH) to form yellow ppt. of iodoform but benzaldehyde does not give this test.
