List of top Chemistry Questions asked in JEE Main

Molarity (M) of an aqueous solution containing \(x \, \text{g}\) of anhyd. CuSO$_4$ in 500 mL solution at 32$^\circ$C is \(2 \times 10^{-1} \, \text{M}\). Its molality will be ____ \( \times 10^{-3} \, \text{m}\) (nearest integer).
[Given density of the solution = 1.25 g/mL.]

When equal volume of 1M HCl and 1M H$_2$SO$_4$ are separately neutralized by excess volume of 1M NaOH solution, X and Y kJ of heat is liberated respectively. The value of Y/X is ____.

How many compounds among the following compounds show inductive, mesomeric as well as hyperconjugation effects?

Given below are two statements:
Statement I: The rate law for the reaction \[ \text{A + B} \rightarrow \text{C} \] is rate\(({r}) = k[{A}]^2[{B}]\). When the concentration of both A and B is doubled, the reaction rate is increased ``x'' times.
Statement II:

The figure is showing ``the variation in concentration against time plot'' for a ``y'' order reaction. The value of $x + y$ is _________.

On reaction of Lead Sulphide with dilute nitric acid which of the following is not formed ?

Identify major product "X" formed in the following reaction :

Compare the energies of following sets of quantum numbers for multielectron system.
(A) n = 4, 1 = 1
(B) n= 4, l = 2
(C) n = 3, l = 1
(D) n = 3, l = 2
(E) n = 4, 1 = 0
Choose the correct answer from the options given below :

What is the structure of C ?

The electronic configuration of Cu(II) is 3d⁹ whereas that of Cu(I) is 3d¹⁰. Which of the following is correct ?

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): The total number of geometrical isomers shown by [Co(en)$_2$Cl$_2$]$^+$ complex ion is three.
Reason (R): [Co(en)$_2$Cl$_2$]$^+$ complex ion has an octahedral geometry.
In the light of the above statements, choose the most appropriate 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): Both rhombic and monoclinic sulphur exist as S$_8$ while oxygen exists as O$_2$.
{Reason (R): Oxygen forms $p\pi$-$p\pi$ multiple bonds with itself and other elements having small size and high electronegativity like C, N, which is not possible for sulphur.
In the light of the above statements, choose the most appropriate answer from the options given below:

For the given compounds, the correct order of increasing \(pK_a\) value :

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R):
Assertion (A): SN$_2$ reaction of C$_6$H$_5$CH$_2$Br occurs more readily than the SN$_2$ reaction of CH$_3$CH$_2$Br.
Reason (R): The partially bonded unhybridized p-orbital that develops in the trigonal bipyramidal transition state is stabilized by conjugation with the phenyl ring.
In the light of the above statements, choose the most appropriate answer from the options given below:

Given below are two statements:
Statement (I): The oxidation state of an element in a particular compound is the charge acquired by its atom on the basis of electron gain enthalpy consideration from other atoms in the molecule.
Statement (II): $p\pi$-$p\pi$ bond formation is more prevalent in second period elements over other periods.
In the light of the above statements, choose the {most appropriate answer from the options given below:

In which one of the following pairs the central atoms exhibit sp$^2$ hybridization?

The F$^-$ ions make the enamel on teeth much harder by converting hydroxyapatite (the enamel on the surface of teeth) into much harder fluoroapatite having the formula:

In the following sequence of reaction, the major products B and C respectively are :

The molar conductivity for electrolytes A and B are plotted against C^1/2 as shown below. Electrolytes A and B respectively are :

Methods used for purification of organic compounds are based on :

Which of the following is the correct structure for the given IUPAC name?
3-Methylpent-2-enal

Which of the following compounds has the highest boiling point?

Total number of species from the following which can undergo disproportionation reaction _______.
$\text{H}_2\text{O}_2, \text{ClO}_3^-, \text{P}_4, \text{Cl}_2, \text{Ag}, \text{Cu}^{+1}, \text{F}_2, \text{NO}_2, \text{K}^+$

Which of the following complex is homoleptic?