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Which among the following is the strongest acid?

In Carius method, halogen containing organic compound is heated with fuming nitric acid in the presence of:

Which one of the following compounds is aromatic in nature?

Given below are two statements :
Statement-I : Ethyl pent-\( 4 \)-yn-oate on reaction with \( \mathrm{CH_3MgBr} \) gives a \( 3^\circ \)-alcohol.
Statement-II : In this reaction one mole of ethyl pent-\( 4 \)-yn-oate utilizes two moles of \( \mathrm{CH_3MgBr} \).
In the light of the above statements, choose the most appropriate answer from the options given below:

Arrange the following conformational isomers of n-butane in order of their increasing potential energy:

Acidic ferric chloride solution on treatment with excess of potassium ferrocyanide gives a Prussian blue coloured colloidal species. It is:

In Carius method for estimation of halogens \( 0.2 \,\text{g} \) of an organic compound gave \( 0.188 \,\text{g} \) of \( \mathrm{AgBr} \). The percentage of bromine in the compound is __________. (Nearest integer) [Atomic mass: \( \mathrm{Ag} = 108 \), \( \mathrm{Br} = 80 \)]

Which one among the following resonating structures is not correct?

Which of the following is an aromatic compound?

The major product of the following reaction, if it occurs by \( \mathrm{S_{N}2} \) mechanism is :

The dihedral angle in staggered form of Newman projection of \( 1, 1, 1, \)-Trichloro ethane is _____ degree. (Round off to the Nearest Integer).

Nitrogen can be estimated by Kjeldahl’s method for which of the following compound ?

An organic compound is subjected to chlorination to get compound \( A \) using \( 5.0 \, \text{g} \) of chlorine. When \( 0.5 \, \text{g} \) of compound \( A \) is reacted with \( \text{AgNO}_3 \) [Carius Method], the percentage of chlorine in compound \( A \) is ________ when it forms \( 0.3849 \, \text{g} \) of \( \text{AgCl} \). (Round off to the Nearest Integer) (Atomic masses of Ag and Cl are \( 107.87 \) and \( 35.5 \) respectively)

The total number of \( \mathrm{C{-}C} \) sigma bond/s in mesityl oxide \(( \mathrm{C_6H_{10}O} )\) is _______. (Round off to the Nearest Integer).

Which one of the following is the major product of the given reaction ?

Choose the correct name for compound given below:

Which one of the following compounds does not exhibit resonance?

Staggered and eclipsed conformers of ethane are :

Which one of the following compounds is non-aromatic?

The number of moles of \( \mathrm{CuO} \), that will be utilized in Dumas method for estimating nitrogen in a sample of \( 57.5 \,\text{g} \) of \( \mathrm{N,N} \)-dimethylaminopentane is __________ \( \times 10^{-2} \). (Nearest integer)

When \( 0.15 \, \text{g} \) of an organic compound was analyzed using Carius method for estimation of bromine, \( 0.2397 \, \text{g} \) of \( \text{AgBr} \) was obtained. The percentage of bromine in the organic compound is ________ . (Nearest integer) [Atomic mass : Silver \( = 108 \), Bromine \( = 80 \)]

The transformation occurring in the Duma's method is given below
\( \mathrm{C_2H_7N} + \left( 2x + \frac{y}{2} \right)\mathrm{CuO} \rightarrow x\mathrm{CO_2} + \frac{y}{2}\mathrm{H_2O} + \frac{z}{2}\mathrm{N_2} + \left( 2x + \frac{y}{2} \right)\mathrm{Cu} \)
The value of \( y \) is _________ . (Integer answer)

Compound with molecular formula \( \mathrm{C_3H_6O} \) can show:

Given below are two statements:
Statement I: The nucleophilic addition of sodium hydrogen sulphite to an aldehyde or a ketone involves proton transfer to form a stable ion.
Statement II: The nucleophilic addition of hydrogen cyanide to an aldehyde or a ketone yields amine as final product.
In the light of the above statements, choose the most appropriate answer from the options given below.

The correct order of stability of given carbocations is :

Choose the correct statement regarding the formation of carbocations A and B given.

Given below are two statements:
Statement I: Hyperconjugation is a permanent effect.
Statement II: Hyperconjugation in ethyl cation \( \displaystyle (\text{CH}_3 - \overset{+}{\text{C}}\text{H}_2) \) involves the overlapping of \( \mathrm{C_{sp^2}-H_{1s}} \) bond with empty \( 2p \) orbital of other carbon.
Choose the correct option:

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): A simple distillation can be used to separate a mixture of propanol and propanone.
Reason (R): Two liquids with a difference of more than \( 20^\circ \mathrm{C} \) in their boiling points can be separated by simple distillations.
In the light of the above statements, choose the most appropriate answer from the options given below:

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JEE Main 2021 31st August Evening Shift

Arrange the following conformational isomers of n-butane in order of their increasing potential energy: