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JEE Main 202623 JanuaryEvening Shift
Exam
JEE Main
Year
2026
Date
23 January
Shift
Evening Shift
Subject
Chemistry
Chapter
Hydrocarbons

JEE Main 2026 · 23 January · Evening Shift · Chemistry · Hydrocarbons

Consider the following reaction of benzene. In compound (Q), the...

Consider the following reaction of benzene.
Consider the following reaction of benzene. In compound (Q), the percentage of oxygen is \_\_\_\_ %. (Nearest integer)
In compound (Q), the percentage of oxygen is ____\_\_\_\_ %. (Nearest integer)

Correct answer

0

Step-by-step solution

Benzene reacts with CH3-CO-CH2-CH2-CO-Cl\text{CH}_3\text{-CO-CH}_2\text{-CH}_2\text{-CO-Cl} in the presence of anhydrous AlCl3\text{AlCl}_3 (Friedel-Crafts acylation) to give product P (a keto-ketone).
P on treatment with aq. NaOH and heating undergoes intramolecular aldol condensation to give a cyclic enone Q.
Molecular mass of Q =157= 157
Percentage of oxygen in Q =16157×100=10.19%≈10%= \frac{16}{157} \times 100 = 10.19\% \approx 10\%
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