List of top Questions asked in JEE Main- 2024

If the area of the region \[ \left\{(x, y) : \frac{a}{x^2} \leq y \leq \frac{1}{x}, \, 1 \leq x \leq 2, \, 0<a<1 \right\} \] is \[ (\log 2) - \frac{1}{7}, \] then the value of $7a - 3$ is equal to:

\[\text{If } \lambda>0, \text{ let } \theta \text{ be the angle between the vectors }\vec{a} = \hat{i} + \lambda \hat{j} - 3 \hat{k} \text{ and } \vec{b} = 3 \hat{i} - \hat{j} + 2 \hat{k}.\text{ If the vectors } \vec{a} + \vec{b} \text{ and } \vec{a} - \vec{b} \text{ are mutually perpendicular, then the value of } (14 \cos \theta)^2 \text{ is equal to.}\]

Given below are two statements:
Statement I: Bromination of phenol in a solvent with low polarity such as CHCl\(_3\) or CS\(_2\) requires a Lewis acid catalyst.
Statement II: The Lewis acid catalyst polarizes the bromine to generate \( \text{Br}^+ \).
In light of the above statements, choose the correct answer from the options given below:

Match the following : 

(a) \([Cr(H_2O)_6]^{+3}\)	(i) \(t^2_{2g}eg^0\)
(b) \([Fe(H_2O)_6]^{+3}\)	(ii) \(t^3_{2g}eg^0\)
\((c) [Ni(H_2O)_6]^{+2}\)	(iii) \(t^3_{2g}eg^2\)
(d) \([V(H_2O)_6]^{+3}\)	(iv) \(t^6_{2g}eg^2\)

Given below are two statements:
Statement (I) : A Buffer solution is the mixture of a salt and an acid or a base mixed in any particular quantities.
Statement (II) : Blood is naturally occurring buffer solution whose pH is maintained by $H_2CO_3/HCO_3^-$ concentrations.
In the light of the above statements, choose the correct answer from the options given below.

The final product A formed in the following multistep reaction sequence is

Which of the following acts as a strong reducing agent? (Atomic number : Ce = 58, Eu = 63, Gd = 64, Lu = 71)

In chromatographic techniques, which of the following follows preferential adsorption?

1. Column chromatography
2. Thin layer chromatography
3. Paper chromatography

What is the structure of C ?

While preparing crystals of Mohr's salt, dil. \(H_2SO_4\) is added to a mixture of ferrous sulphate and ammonium sulphate, before dissolving this mixture in water, dil. \(H_2SO_4\) is added here to:

The correct order of the first ionization enthalpy is

The solution from the following with highest depression in freezing point/lowest freezing point is

A first row transition metal in its +2 oxidation state has a spin-only magnetic moment value of 3.86 BM. The atomic number of the metal is

Match List I with List II

LIST-I (Cell)	LIST-II (Use/Property/Reaction)
A. Leclanche cell	IV. Reaction at anode Zn → Zn2+ + 2e-
B. Ni-Cd cell	III. Rechargeable
C. Fuel cell	I. Converts energy of combustion into electrical energy
D. Mercury cell	II. Does not involve any ion in solution and is used in hearing aids

Choose the correct answer from the options given below:

The correct statements from following are:
A. The strength of anionic ligands can be explained by crystal field theory. 
B. Valence bond theory does not give a quantitative interpretation of kinetic stability of coordination compounds. 
C. The hybridization involved in formation of \([Ni(CN)_4​]^{2−}\) complex is \(dsp^2\). 
D. The number of possible isomer(s) of \(cis-[PtCl_2​(en)_2​]^{2+}\) is one.
Choose the correct answer from the options given below:

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): NH$_3$ and NF$_3$ molecule have pyramidal shape with a lone pair of electrons on nitrogen atom. The resultant dipole moment of NH$_3$ is greater than that of NF$_3$.
Reason (R): In NH$_3$, the orbital dipole due to lone pair is in the same direction as the resultant dipole moment of the N$-$H bonds. F is the most electronegative element.
In the light of the above statements, choose the correct answer from the options given below:

The technique used for purification of steam volatile water immiscible substance is:

Which of the following compound will most easily be attacked by an electrophile?

The set of meta directing functional groups from the following sets is:

Identify the reagents used for the following conversion

Choose the polar molecule from the following:

Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R :
Assertion A : Aryl halides cannot be prepared by replacement of hydroxyl group of phenol by halogen atom.
Reason R : Phenols react with halogen acids violently. In the light of the above statements.
Choose the most appropriate from the options given below:

Quantum number for outermost electron of K-atom are given by

Identify correct statements from below:
A. The chromate ion is square planar. 
B. Dichromates are generally prepared from chromates. 
C. The green manganate ion is diamagnetic. 
D. Dark green coloured \(K_2​MnO_4\)​ disproportionates in a neutral or acidic medium to give permanganate. 
E. With increasing oxidation number of transition metal, ionic character of the oxides decreases. 
Choose the correct answer from the options given below: