Which simple chemical test is used to distinguish between ethanal and propanal?

Iodoform test

The correct answer is option 1. Iodoform test.

The iodoform test is used to detect aldehydes and ketones groups.

Tollens' test, also known as the silver-mirror test is used to distinguish between an aldehyde and a ketone.

Fehling's test is used for the estimation or detection of reducing sugars and non-reducing sugars.

Lucas test is used to differentiate and categorize primary, secondary, and tertiary alcohols.