List of top Questions asked in JEE Main

Match List-I with the List-II
List-I
(Precipitating reagent and
conditions)		List-II
(Cation)
(A) \(NH_4Cl + NH_4OH\)(I) Mn2+
(B) \(NH_4OH + Na_2CO_3\)(II) Pb2+
(C) \(NH_4OH + NH_4Cl + H_2S gas\)(III) Al3+
(D) dilute HCl(IV) Sr2+
Choose the correct answer from the options given below:
Consider the following complexes:
\([CoCl(NH_3)_5]^{2+}\) (A)
\([Co(CN)_6]^{3-}\) (B)
\([Co(NH_3)_5(H_2O)]^{3+}\) (C)
\([Cu(H_2O)_4]^{2+}\) (D)
The correct order of A, B, C, and D in terms of wavenumber of light absorbed is:
Which of the following material is not a semiconductor.
In Reimer - Tiemann reaction, phenol is converted into salicylaldehyde through an intermediate. The structure of intermediate is ______.
Which of the following statements are correct ?
A. Glycerol is purified by vacuum distillation because it decomposes at its normal boiling point
B. Aniline can be purified by steam distillation as aniline is miscible in water.
C. Ethanol can be separated from ethanol water mixture by azeotropic distillation because it forms azeotrope.
D. An organic compound is pure, if mixed M.P. is remained same.
Choose the most appropriate answer from the options given below :
Match List-I with the List-II
List-I
(Hybridization)		List-II
(Orientation in
Space)
(A) sp3(I) Trigonal
bipyramidal
(B) dsp2(II) Octahedral
(C) sp3d(III) Tetrahedral
(D) sp3d2(IV) Square planar
Choose the correct answer from the options given below:
Which of the following is metamer of the given compound (X) ?
Match List-I with the List-II
List-I
(Molecule / Species)		List-II
(Property / Shape)
(A) \(SO_2Cl_2\)(I) Paramagnetic
(B) NO(II) Diamagnetic
(C) \(NO^{-}_{2}\)(III) Tetrahedral
(D) \(I^{-}_{3}\)(IV) Linear
Choose the correct answer from the options given below:
Functional group present in sulphonic acid is :
For three vectors \( \vec{A} = (-xi - 6j - 2k), \) \( \vec{B} = (-i + 4j + 3k) \) and \( \vec{C} = (-8i - j + 3k), \) if \( \vec{A} \cdot (\vec{B} \times \vec{C}) = 0, \) then value of x is ___________.
A circular coil having 200 turns, $2.5 \times 10^{-4} \text{ m}^2$ area and carrying 100 $\mu$A current is placed in a uniform magnetic field of 1 T. Initially the magnetic dipole moment ($\vec{M}$) was directed along $\vec{B}$. Amount of work, required to rotate the coil through $90^\circ$ from its initial orientation such that $\vec{M}$ becomes perpendicular to $\vec{B}$, is ________ $\mu$J.
Radius of a certain orbit of hydrogen atom is 8.48 Å. If energy of electron in this orbit is E/x, then x = ______.
(Given a0 = 0.529Å, E = energy of electron in ground state)
The refractive index of prism is µ = √3 and the ratio of the angle of minimum deviation to the angle of prism is one. The value of angle of prism is ______o.
When a DC voltage of 100 V is applied to an inductor, a DC current of 5 A flows through it. When an AC voltage of 200 V peak value is connected to the inductor, its inductive reactance is found to be \( 20\sqrt{3} \, \Omega \). The power dissipated in the circuit is _________ W.
A big drop is formed by coalescing 1000 small droplets of water. The ratio of surface energy of 1000 droplets to that of energy of the big drop is \( \frac{10}{x} \).The value of x is _________.
If the radius of earth is reduced to three-fourth of its present value without change in its mass then value of duration of the day of earth will be ______ hours 30 minutes.
\[\text{Let } A = \begin{bmatrix} 2 & 1 & 2 \\ 6 & 2 & 11 \\ 3 & 3 & 2 \end{bmatrix} \text{ and } P = \begin{bmatrix} 1 & 2 & 0 \\ 5 & 0 & 2 \\ 7 & 1 & 5 \end{bmatrix}.\]The sum of the prime factors of \( |P^{-1}AP - 2I| \) is equal to.
In photoelectric experiment energy of 2.48 eV irradiates a photo sensitive material. The stopping potential was measured to be 0.5 V. Work function of the photo sensitive material is :
A small ball of mass $m$ and density $\rho$ is dropped in a viscous liquid of density $\rho_0$. After some time, the ball falls with constant velocity. The viscous force on the ball is:
An element \(\triangle l=\triangle x \hat i\) is placed at the origin and carries a large current I = 10A. The magnetic field on the y-axis at a distance of 0.5 m from the elements x of 1 cm length is :
The magnetic field on the y-axis at a distance of 0.5 m
A light string passing over a smooth light pulley connects two blocks of masses \(m_1\)​ and \(m_2\)​ (where \(m_2​>m_1\)​). If the acceleration of the system is $\frac{g}{\sqrt{2}}$, then the ratio of the masses $\frac{m_1}{m_2}$ is:
A sample contains a mixture of helium and oxygen gas. The ratio of root mean square speed of helium and oxygen in the sample is:
The correct truth table for the following logic circuit is :
logic circuit
Given below are two statements:
Statement I: In an LCR series circuit, current is maximum at resonance. 
Statement II: Current in a purely resistive circuit can never be less than that in a series LCR circuit when connected to the same voltage source. 
In the light of the above statements, choose the correct from the options given below.
The value of unknown resistance (x) for which the potential difference between B and D will be zero in the arrangement shown, is :