Give the simple chemical test to distinguish between ethanal and propanal.

Explanation

Distinguishing test between ethanal and propanal lodoform test Ethanal because of the presence of `CH_(3)CO-` skeleton gives iodoform test whereas propanal due to the absence of such a skeleton does not.
`underset("Acetaldehyde")underset("or")underset("Ethanal")(CH_(3)CHO)+4NaOH +3I_(2)to underset("(yellow ppt)")underset("Iodoform")(CHI_(3)darr)+underset("Sodium formate")(HCOONa)+underset("iodine")underset("Sodium")(3NaI)+3H_(2)O`
`underset("Propanal")(CH_(3)CH_(2)CHO) +4NaOH+3I_(2) to ` No reaction