List of top Chemistry Questions asked in JEE Main

A colloidal system consisting of a gas dispersed in a solid is called a/an :
A certain orbital has \(n = 4\) and \(m_L = -3\). The number of radial nodes in this orbital is ____________. (Round off to the Nearest Integer).
The INCORRECT statement(s) about heavy water is (are)

(A) used as a moderator in nuclear reactor

(B) obtained as a by-product in fertilizer industry

(C) used for the study of reaction mechanism

(D) has a higher dielectric constant than water

Choose the correct answer from the options given below :
Which of the following reaction is an example of ammonolysis?
With respect to drug-enzyme interaction, identify the wrong statement.
Which of the following is correct structure of tyrosine?
Which of the following is an aromatic compound?
Mesityl oxide is a common name of :
Given below are two statements :

Statement I : Retardation factor (Rf) can be measured in meter/centimeter.

Statement II : Rf value of a compound remains constant in all solvents.

Choose the most appropriate answer from the options given below :
Given below are two statements :
Statement I : Potassium permanganate on heating at 573K forms potassium manganate.
Statement II : Both potassium permanganate and potassium manganate are tetrahedral and paramagnetic in nature.
In the light of the above statements, choose the most appropriate answer from the options given below :
A central atom in a molecule has two lone pairs of electrons and forms three single bonds. The shape of this molecule is :
Hoffmann bromomide degradation of benzamide gives product A, which upon heating with \(\mathrm{CHCl_3}\) and NaOH gives product B.
The structures of A and B are :

The above reaction requires which of the following reaction conditions?

Product "A" in the above chemical reaction is :
Which of the following compound CANNOT act as a Lewis base?

The product "A" in the above reaction is :
What is the spin-only magnetic moment value (BM) of a divalent metal ion with atomic number 25, in it's aqueous solution?
The absolute value of the electron gain enthalpy of halogens satisfies :
At 363 K, the vapour pressure of A is 21 kPa and that of B is 18 kPa. One mole of A and 2 moles of B are mixed. Assuming that this solution is ideal, the vapour pressure of the mixture is ___________ kPa. (Round off to the Nearest Integer).
Ga (atomic mass 70 u) crystallizes in a hexagonal close packed structure. The total number of voids in 0.581 g of Ga is __________ \(\times\) \(10^{21}\). (Round off to the Nearest Integer). [Given : \(\mathrm{N_A}\) = 6.023 \(\times\) \(10^{23}\)]
The correct statements about \(\mathrm{H_2O_2}\) are :

(A) used in the treatment of effluents.

(B) used as both oxidising and reducing agents.

(C) the two hydroxyl groups lie in the same plane.

(D) miscible with water.

Choose the correct answer from the options given below :
At 25\(^\circ\)C, 50 g of iron reacts with HCl to form \(\mathrm{FeCl_2}\). The evolved hydrogen gas expands against a constant pressure of 1 bar. The work done by the gas during this expansion is _________ J. (Round off to the Nearest Integer).

[Given : R = 8.314 J mol\(^{-1}\) K\(^{-1}\). Assume, hydrogen is an ideal gas] [Atomic mass of Fe is 55.85 u]
A and B decompose via first order kinetics with half-lives 54.0 min and 18.0 min respectively. Starting from an equimolar non reactive mixture of A and B, the time taken for the concentration of A to become 16 times that of B is _________ min. (Round off to the Nearest Integer).
The INCORRECT statements below regarding colloidal solutions is :
In Duma's method of estimation of nitrogen, 0.1840 g of an organic compound gave 30 mL of nitrogen collected at 287 K and 758 mm of Hg pressure. The percentage composition of nitrogen in the compound is __________. (Round off to the Nearest Integer). [Given : Aqueous tension at 287 K = 14 mm of Hg]