CBSE Class 12-science Answered

Ethanol is a primary alcohol whereas propan-2-ol  is a secondary alcohol

And secondary alcohol gives Iodoform test whereas Primary alcohol does not give this test.

Here, is  the explanation of  the Iodoform test given by propan-2-ol:-

Addition of I₂(aq) (usually I₂ dissolved in KI, shown here reacting with 2-propanol
2 NaOH + I₂ + CH₃CH(OH)CH₃ ? 2 NaI + CH₃COCH₃ + 2 H₂O
oxidizes the hydroxyl group to a ketone,

The ketone formed reacts with the I2(aq) in a substitution reaction to produce a triiodoketone, for example triiodoacetone.
CH₃COCH₃ + 3I₂ ? CH₃COCI₃ + 3HI