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Consider the above reaction and identify the product \( P \):

In the above reaction, \( 3.9 \, \text{g} \) of benzene on nitration gives \( 4.92 \, \text{g} \) of nitrobenzene. The percentage yield of nitrobenzene in the above reaction is ______ \( \% \). (Round off to the Nearest Integer).
[Given atomic mass : \( \mathrm{C:12.0 \, u , \ H:1.0 \, u , \ O:16.0 \, u , \ N:14.0 \, u} \)]

Consider the above chemical reaction. The total number of stereoisomers possible for Product ‘P’ is ________.

Identify the reagent(s) ‘A’ and condition(s) for the reaction:

For above chemical reactions, identify the correct statement from the following.

Presence of which reagent will affect the reversibility of the following reaction, and change it to a irreversible reaction:

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : Treatment of bromine water with propene yields \( 1 \)-bromopropan-\( 2 \)-ol.
Reason (R) : Attack of water on bromonium ion follows Markovnikov rule and results in \( 1 \)-bromopropan-\( 2 \)-ol.
In the light of the above statements, choose the most appropriate answer from the options given below:

An organic compound ‘A’ \( \mathrm{C_4H_8} \) on treatment with \( \mathrm{KMnO_4/H^+} \) yields compound ‘B’ \( \mathrm{C_3H_6O} \). Compound ‘A’ also yields compound ‘B’ on ozonolysis. Compound ‘A’ is:

Metallic sodium does not react normally with:

Product “A” in the above chemical reaction is:

In the following sequence of reactions, the final product \( D \) is:

Which one of the following carbonyl compounds cannot be prepared by addition of water on an alkyne in the presence of \( \mathrm{HgSO_4} \) and \( \mathrm{H_2SO_4} \)?

The major product formed in the following reaction is:

Match List-I with List-II:

Choose the most appropriate match:

Excess of isobutane on reaction with \( \mathrm{Br_2} \) in presence of light at \( 125^\circ\mathrm{C} \) gives which one of the following, as the major product?

A chloro compound “A”.
(i) Forms aldehydes on ozonolysis followed by the hydrolysis.
(ii) When vaporized completely, \( 1.53 \, \text{g} \) of A, gives \( 448 \, \text{mL} \) of vapour at STP.
The number of carbon atoms in a molecule of compound A is ______.

In the above reaction, the reagent “\( A \)” is:

Considering the above chemical reaction, identify the product “X”:

The stereoisomers that are formed by electrophilic addition of bromine to trans-but-\( 2 \)-ene is:

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JEE Main 2021 24th Feb Evening Shift

Which one of the following carbonyl compounds cannot be prepared by addition of water on an alkyne in the presence of \( \mathrm{HgSO_4} \) and \( \mathrm{H_2SO_4} \)?