List of top Questions asked in JEE Main

Match List - I with List - II:

List - I

List - II

(A) Adenine

(I)

(B) Cytosine

(II)

(C) Thymine

(III)

(D) Uracil

(IV)

 

Choose the correct answer from the options given below:

Find the compound \( A \) from the following reaction sequences: \[ A \xrightarrow{\text{aqua regia}} B \xrightarrow{(1) \, \text{KNO}_3, \, \text{NH}_4\text{OH}} \text{yellow ppt}. \]
Given below are two statements:

Statement I: Experimentally determined oxygen-oxygen bond lengths in the \( O_2 \) are found to be the same and the bond length is greater than that of a \( O=O \) (double bond) but less than that of a single \( O-O \) bond.

Statement II: The strong lone pair-lone pair repulsion between oxygen atoms is solely responsible for the fact that the bond length in ozone is smaller than that of a double bond \( O=O \) but more than that of a single bond \( O-O \).

In light of the above statements, choose the correct answer from the options given below:

Identify correct statement/s: 
(A) \( -\text{OCH}_3 \) and \( -\text{NHCOCH}_3 \) are activating groups. 
(B) \( -\text{CN} \) and \( -\text{OH} \) are meta directing groups. 
(C) \( -\text{CN} \) and \( -\text{SO}_3\text{H} \) are meta directing groups.
(D) Activating groups act as ortho- and para-directing groups.
(E) Halides are activating groups. 
Choose the correct answer from the options given below:

The successive 5 ionisation energies of an element are 800, 2427, 3658, 25024 and 32824 kJ/mol, respectively. By using the above values, predict the group in which the above element is present:
The conditions and consequences that favour the \( t_{2g}^3 e_g^1 \) configuration in a metal complex are:

Match List - I with List - II.

The product (P) formed in the following reaction is:

The sum of sigma (σ) and pi (π) bonds in Hex-1,3-dien-5-yne is:
Which among the following halides will generate the most stable carbocation in a nucleophilic substitution reaction?
Total number of sigma (\( \sigma \)) and pi (\( \pi \)) bonds respectively present in hex-1-en-4-yne are:
Which one of the following reaction sequences will give an azo dye?
Isomeric hydrocarbons \( \rightarrow \) negative Baeyer's test (Molecular formula \( \text{C}_9\text{H}_{12} \)). The total number of isomers from above with four different non-aliphatic substitution sites is -

The most stable carbocation from the following is: 

Match the Compounds (List - I) with the appropriate Catalyst/Reagents (List - II) for their reduction into corresponding amines.

The alkane from below having two secondary hydrogens is:
Which of the following molecules hydrolyzes fast?
Which of the following is the correct order of basic strength of amines in aqueous medium?
In 3, 3-dimethylhex-1-en-4-yne, the number of sp, sp² and sp³ carbon atoms, respectively are:
Transition metal belonging to the 3d series having the lowest enthalpy of atomization in its most stable oxidation state forms oxide \( \text{MO} \). Nature of the oxide is:
Given below are two statements: - Assertion (A): Sodium on reaction with alcohols liberates \( \text{H}_2 \) gas. - Reason (R): Alcohols are acidic in nature. In the light of the above statements, choose the correct answer from the options below:
Consider the following sequence of reactions given below: $ \text{Br-C}_6\text{H}_5 \xrightarrow{\text{alc. KOH}} \text{C}_6\text{H}_4 \xrightarrow{\text{NaNH}_2} \text{C}_6\text{H}_3 \xrightarrow{Hg^{2+}} \text{C}_6\text{H}_2 \xrightarrow{Zn-Hg} P $ The product P is:

The correct sequence of reagents to be added for the following conversion is:

The correct IUPAC name of the product is:

Match List-I with List-II and select the correct option: