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MODEL PAPER 2025 — Chemistry STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 ScienceChemistryMODEL PAPER 20253 Marks
Question
An organic compound 'X', does not undergo aldol condensation. However 'X' with compound 'Y' in the presence of a strong base react to give the compound 1,3-diphenylprop-2-en-1-one.
a. Identify 'X' and 'Y'
b. Write the chemical reaction involved.
c. Give one chemical test to distinguish between X and Y.
✓

Answer

(a) Compound 'X' = Benzaldehyde, Compound Y = Acetophenone
(b)
Image
Chemical test to distinguish between X and Y is the Tollen Test.
(c) Benzaldehyde undergoes Silver mirror test with Tollen reagent and forms silver mirror. However Acetophenone does not react with Tollen Reagent.

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