How many alcohols of molecular formula C5H12O give a yellow precipitate with NaOH/I2? Count constitutional isomers only (no stereoisomers).

JEE Main levelSingle correct optionDifficulty 2 of 3si129

How many alcohols of molecular formula $C X_{5} H X_{12} O$ give a yellow precipitate with $NaOH / I X_{2}$ ? Count constitutional isomers only (no stereoisomers).

Of the eight

C X_{5} H X_{12} O

alcohols, only those with a

CH X_{3} CH (OH) X^{-}

group give the iodoform test. These are pentan-2-ol and 3-methylbutan-2-ol. Pentan-3-ol has

CH X_{3} CH X_{2} CH (OH) X^{-}

and fails. The count is 2.