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MODEL PAPER 6 — Chemistry STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceChemistryMODEL PAPER 61 Mark
Question
Assertion (A): Formaldehyde cannot be prepared by Rosenmund's reduction.
Reason (R): Acid chlorides can be reduced into aldehydes with hydrogen in boiling xylene using palladium or platinum as a catalyst supported on barium sulphate. This is known as Rosenmund's reduction.
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Answer

(b) Both A and R are true but R is not the correct explanation of A.
Explanation: HCHO cannot be prepared by Rosenmund's reduction because formyl chloride is unstable at room temperature.

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