Same chapter3 marksDifficulty: Medium
Arrange acetic acid, chloroacetic acid and trichloroacetic acid in increasing order of acidity and give the reason.
Aldehydes, Ketones and Carboxylic Acids
3 marksDifficulty: Medium
What is the iodoform test, and which compounds give a positive result?
Original Khojo Papers practice question — not from a past board paper.
Answer
The compound is warmed with iodine and sodium hydroxide; a yellow precipitate of iodoform with its characteristic smell shows a positive result. It is given by ethanal, by any methyl ketone, and by ethanol and any alcohol with the CH3CH(OH)− group, because these are oxidised to a methyl ketone in the conditions of the test.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Propanone gives a positive test but propanal does not.
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