Two compounds A and B with same molecular formula C3H5O undergo Grignard-s reaction with methylmagnesium bromide to give products C and D- Products C and D show following chemical tests- Test C D- Ceric ammonium Positive Positive- nitrate Test - Lucas text Turbidity obtained Turbidity obtained- after five minutes immediately- Iodoform Test Positive Negative- -C and D respectively are

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Structural and Physical Properties of Carbonyls

Two compounds...

Question

Two compounds A and B with same molecular formula $(C_{3} H_{5} O)$ undergo Grignard's reaction with methylmagnesium bromide to give products C and D. Products C and D show following chemical tests.
$\begin{matrix} Test & C & D Ceric ammonium & Positive & Positive nitrate Test Lucas text & Turbidity obtained & Turbidity obtained after five minutes & immediately Iodoform Test & Positive & Negative \end{matrix}$
C and D respectively are

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Solution

The correct option is D
Lucas test is used to distinguish between $1^{\circ}, 2^{\circ} and 3^{\circ} alcohols .$
Lucas reagent is a solution of anhydrous zinc chloride in concentrated hydrochloric acid.
Tertiary alcohols react immediately with Lucas reagent.
Secondary alcohols react within 10-15 minutes (depending on their solubility).
Primary alcohols do not react appreciably with Lucas reagent at room temperature.
Thus, compound C is secondary alcohol and compound (D) is tertiary alcohol.

Iodoform test is used to check the presence of carbonyl compounds with the structure $R - C O - C H_{3}$ or alcohols with the structure $R - C H (O H) - C H_{3}$ in a given unknown substance.
Hence,
can give positive CAN test, iodoform test, and with Lucas reagent it takes 5 minutes to give turbidity.
cannot give iodoform test but can give CAN test and Lucas test.

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