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COMEDK202510 May 2025Evening ShiftChemistryAlcohols Phenols and EthersActual

Which one of the following compounds will give a yellow precipitate when reacted with I ₂ / NaOH ?

Options

  1. AC ₆ H ₅ CH ₂ OH
  2. B( CH ₃ )₃ C - OH
  3. CC ₆ H ₅ OH
  4. DC ₆ H ₅ CHOH - CH ₃

Correct answer

D. C ₆ H ₅ CHOH - CH ₃

Step-by-step solution

The iodoform test is given by compounds containing the CH ₃ CO - group or the CH ₃ CH(OH) - group. These groups are oxidized to the methyl ketone group, which then reacts with I ₂ / NaOH to form a yellow precipitate of iodoform ( CHI ₃ ). Analyzing the options: 1. C ₆ H ₅ CH ₂ OH is a primary alcohol and does not contain the required CH ₃ CH(OH) - structural unit. 2. ( CH ₃)₃ C - OH is a tertiary alcohol and cannot be oxidized to a methyl ketone. 3. C ₆ H ₅ OH (phenol) does not contain the CH ₃ CH(OH) - or CH ₃ CO

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