JEE Main 2020 January 7 Shift 2 Question Paper is available here with solutions PDF and detailed solutions for every question. NTA conducted the second shift on January 7, 2020, from 2:30 PM to 5:30 PM. The JEE Main 2020 Paper 1 (B.E./B.Tech) question paper includes the following:

  • 75 questions in a 3-hour CBT Mode: 25 each from Mathematics, Physics and Chemistry
  • Section A: 20 multiple choice questions (MCQs) per subject, 4 marks each
  • Section B: 5 numerical value questions per subject, all compulsory, 4 marks each
  • Marking: +4 for a correct answer, -1 for an incorrect MCQ, 0 for an unattempted question; no negative marking for numerical value questions
  • Maximum marks: 300 (100 per subject)

JEE Main 2020 January 7 Shift 2 Question Paper with Solution PDF

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JEE Main 2020 January 7 Shift 2 Questions with Solutions


Mathematics - Section A (Q1 - Q20)

Question 1:

The area (in sq. units) of the region
{(x, y) \( \in \) R2 | 4x2 \( \le \) y \( \le \) 8x + 12} is :

  • (A) \( {{125} \over 3} \)
  • (B) \( {{128} \over 3} \)
  • (C) \( {{127} \over 3} \)
  • (D) \( {{124} \over 3} \)

Question 2:

Let y = y(x) be the solution curve of the differential equation,

\( \left( {{y^2} - x} \right){{dy} \over {dx}} = 1 \), satisfying y(0) = 1. This curve intersects the x-axis at a point whose abscissa is :

  • (A) 2 + e
  • (B) -e
  • (C) 2
  • (D) 2 - e

Question 3:

Let \( {a_1} \) , \( {a_2} \) , \( {a_3} \) ,....... be a G.P. such that
\( {a_1} \) < 0, \( {a_1} \) + \( {a_2} \) = 4 and \( {a_3} \) + \( {a_4} \) = 16.
If \( \sum\limits_{i = 1}^9 {{a_i}} = 4\lambda \), then \( \lambda \) is equal to:

  • (A) 171
  • (B) -171
  • (C) -513
  • (D) \( {{511} \over 3} \)

Question 4:

The number of ordered pairs (r, k) for which
6.35Cr = (k2 - 3). 36Cr + 1, where k is an integer, is :

  • (A) 6
  • (B) 3
  • (C) 2
  • (D) 4

Question 5:

Let \( \overrightarrow a \) , \( \overrightarrow b \) and \( \overrightarrow c \) be three unit vectors such that
\( \overrightarrow a + \vec b + \overrightarrow c = \overrightarrow 0 \). If \( \lambda = \overrightarrow a .\vec b + \vec b.\overrightarrow c + \overrightarrow c .\overrightarrow a \) and
\( \overrightarrow d = \overrightarrow a \times \vec b + \vec b \times \overrightarrow c + \overrightarrow c \times \overrightarrow a \), then the ordered pair, \( \left( {\lambda ,\overrightarrow d } \right) \) is equal to :

  • (A) \( \left( {{3 \over 2},3\overrightarrow a \times \overrightarrow c } \right) \)
  • (B) \( \left( { - {3 \over 2},3\overrightarrow c \times \overrightarrow b } \right) \)
  • (C) \( \left( { - {3 \over 2},3\overrightarrow a \times \overrightarrow b } \right) \)
  • (D) \( \left( {{3 \over 2},3\overrightarrow b \times \overrightarrow c } \right) \)

Question 6:

If \( \theta \)1 and \( \theta \)2 be respectively the smallest and the largest values of \( \theta \) in (0, 2\( \pi \)) - {\( \pi \)} which satisfy the equation,
2cot2\( \theta \) - \( {5 \over {\sin \theta }} \) + 4 = 0, then
\( \int\limits_{{\theta _1}}^{{\theta _2}} {{{\cos }^2}3\theta d\theta } \) is equal to :

  • (A) \( {\pi \over 9} \)
  • (B) \( {{2\pi } \over 3} \)
  • (C) \( {{\pi } \over 3} \)
  • (D) \( {\pi \over 3} + {1 \over 6} \)

Question 7:

The value of \( \alpha \) for which
\( 4\alpha \int\limits_{ - 1}^2 {{e^{ - \alpha \left| x \right|}}dx} = 5 \), is:

  • (A) \( {\log _e}2 \)
  • (B) \( {\log _e}\sqrt 2 \)
  • (C) \( {\log _e}\left( {{4 \over 3}} \right) \)
  • (D) \( {\log _e}\left( {{3 \over 2}} \right) \)

Question 8:

Let ƒ(x) be a polynomial of degree 5 such that x = ±1 are its critical points.

If \( \mathop {\lim }\limits_{x \to 0} \left( {2 + {{f\left( x \right)} \over {{x^3}}}} \right) = 4 \), then which one of the following is not true?

  • (A) ƒ(1) - 4ƒ(-1) = 4.
  • (B) x = 1 is a point of minima and x = -1 is a point of maxima of ƒ.
  • (C) x = 1 is a point of maxima and x = -1 is a point of minimum of ƒ.
  • (D) ƒ is an odd function.

Question 9:

The coefficient of \( x^7 \) in the expression \( \left(1+x\right)^{10}+x\left(1+x\right)^{9}+x^{2}\left(1+x\right)^{8}+...+x^{10} \) is :

  • (A) \( 420 \)
  • (B) \( 330 \)
  • (C) \( 210 \)
  • (D) \( 120 \)

Question 10:

The locus of the mid-points of the perpendiculars drawn from points on the line, x = 2y to the line x = y is :

  • (A) 3x - 2y = 0
  • (B) 7x - 5y = 0
  • (C) 2x - 3y = 0
  • (D) 5x - 7y = 0

Question 11:

Let \( \alpha \) and \( \beta \) be the roots of the equation x2 - x - 1 = 0.
If pk = \( {\left( \alpha \right)^k} + {\left( \beta \right)^k} \) , k \( \ge \) 1, then which one of the following statements is not true?

  • (A) (p1 + p2 + p3 + p4 + p5) = 26
  • (B) p5 = 11
  • (C) p3 = p5 – p4
  • (D) p5 = p2 · p3

Question 12:

Let y = y(x) be a function of x satisfying

\( y\sqrt {1 - {x^2}} = k - x\sqrt {1 - {y^2}} \) where k is a constant and

\( y\left( {{1 \over 2}} \right) = - {1 \over 4} \). Then \( {{dy} \over {dx}} \) at x = \( {1 \over 2} \), is equal to :

  • (A) \( {2 \over {\sqrt 5 }} \)
  • (B) \( - {{\sqrt 5 } \over 2} \)
  • (C) \( {{\sqrt 5 } \over 2} \)
  • (D) \( - {{\sqrt 5 } \over 4} \)

Question 13:

If \( {{3 + i\sin \theta } \over {4 - i\cos \theta }} \), \( \theta \) \( \in \) [0, 2\( \theta \)], is a real number, then an argument of
sin\( \theta \) + icos\( \theta \) is :

  • (A) \( \pi - {\tan ^{ - 1}}\left( {{3 \over 4}} \right) \)
  • (B) \( - {\tan ^{ - 1}}\left( {{3 \over 4}} \right) \)
  • (C) \( {\tan ^{ - 1}}\left( {{4 \over 3}} \right) \)
  • (D) \( \pi - {\tan ^{ - 1}}\left( {{4 \over 3}} \right) \)

Question 14:

In a workshop, there are five machines and the probability of any one of them to be out of service on a day is \( {{1 \over 4}} \) . If the probability that at most two machines will be out of service on the same day is \( {\left( {{3 \over 4}} \right)^3}k \), then k is equal to :

  • (A) \( {{{17} \over 4}} \)
  • (B) \( {{{17} \over 2}} \)
  • (C) \( {{{17} \over 8}} \)
  • (D) 4

Question 15:

Let A, B, C and D be four non-empty sets. The contrapositive statement of "If A \( \subseteq \) B and B \( \subseteq \) D, then A \( \subseteq \) C" is :

  • (A) If A ⊈ C, then A ⊈ B or B ⊈ D
  • (B) If A ⊈ C, then A ⊈ B and B \( \subseteq \) D
  • (C) If A \( \subseteq \) C, then B \( \subset \) A or D \( \subset \) B
  • (D) If A ⊈ C, then A \( \subseteq \) B and B \( \subseteq \) D

Question 16:

Let A = [aij] and B = [bij] be two 3 × 3 real matrices such that bij = (3)(i+j-2)aji, where i, j = 1, 2, 3. If the determinant of B is 81, then the determinant of A is:

  • (A) 3
  • (B) \( {1 \over 3} \)
  • (C) \( {1 \over 9} \)
  • (D) \( {1 \over {81}} \)

Question 17:

The value of c in the Lagrange's mean value theorem for the function
ƒ(x) = x3 - 4x2 + 8x + 11, when x \( \in \) [0, 1] is:

  • (A) \( {2 \over 3} \)
  • (B) \( {{\sqrt 7 - 2} \over 3} \)
  • (C) \( {{4 - \sqrt 5 } \over 3} \)
  • (D) \( {{4 - \sqrt 7 } \over 3} \)

Question 18:

Let the tangents drawn from the origin to the circle,
x2 + y2 - 8x - 4y + 16 = 0 touch it at the points A and B. The (AB)2 is equal to :

  • (A) \( {{56} \over 5} \)
  • (B) \( {{32} \over 5} \)
  • (C) \( {{52} \over 5} \)
  • (D) \( {{64} \over 5} \)

Question 19:

If the sum of the first 40 terms of the series,
3 + 4 + 8 + 9 + 13 + 14 + 18 + 19 + ..... is (102)m, then m is equal to :

  • (A) 20
  • (B) 5
  • (C) 10
  • (D) 25

Question 20:

If 3x + 4y = 12\( \sqrt 2 \) is a tangent to the ellipse
\( {{{x^2}} \over {{a^2}}} + {{{y^2}} \over 9} = 1 \) for some \( a \) \( \in \) R, then the distance between the foci of the ellipse is :

  • (A) \( 2\sqrt 5 \)
  • (B) \( 2\sqrt 7 \)
  • (C) 4
  • (D) \( 2\sqrt 2 \)

Mathematics - Section B (Q21 - Q25)

Question 21:

If the function ƒ defined on \( \left( { - {1 \over 3},{1 \over 3}} \right) \) by

f(x) = \( \left\{ {\matrix{ {{1 \over x}{{\log }_e}\left( {{{1 + 3x} \over {1 - 2x}}} \right),} & {when\,x \ne 0} \cr {k,} & {when\,x = 0} \cr } } \right. \)

is continuous, then k is equal to_______.


Question 22:

If the system of linear equations,
x + y + z = 6
x + 2y + 3z = 10
3x + 2y + \( \lambda \)z = \( \mu \)
has more than two solutions, then \( \mu \) - \( \lambda \)2 is equal to ______.


Question 23:

If the mean and variance of eight numbers 3, 7, 9, 12, 13, 20, x and y be 10 and 25 respectively, then x.y is equal to _______.


Question 24:

If the foot of the perpendicular drawn from the point (1, 0, 3) on a line passing through (\( \alpha \), 7, 1) is \( \left( {{5 \over 3},{7 \over 3},{{17} \over 3}} \right) \), then \( \alpha \) is equal to______.


Question 25:

Let X = {n \( \in \) N : 1 \( \le \) n \( \le \) 50}. If
A = {n \( \in \) X: n is a multiple of 2} and
B = {n \( \in \) X: n is a multiple of 7}, then the number of elements in the smallest subset of X containing both A and B is ________.


Physics - Section A (Q26 - Q45)

Question 26:

Mass per unit area of a circular disc of radius \( a \) depends on the distance r from its centre as \( \sigma \left( r \right) \) = A + Br . The moment of inertia of the disc about the axis, perpendicular to the plane and assing through its centre is:

  • (A) \( 2\pi {a^4}\left( {{A \over 4} + {{aB} \over 5}} \right) \)
  • (B) \( \pi {a^4}\left( {{A \over 4} + {{aB} \over 5}} \right) \)
  • (C) \( 2\pi {a^4}\left( {{{aA} \over 4} + {B \over 5}} \right) \)
  • (D) \( 2\pi {a^4}\left( {{A \over 4} + {B \over 5}} \right) \)

Question 27:

An emf of 20 V is applied at time t = 0 to a circuit containing in series 10 mH inductor and 5 \( \Omega \) resistor. The ratio of the currents at time t = \( \infty \) and at t = 40 s is close to : (Take e2 = 7.389)

  • (A) 1.06
  • (B) 0.84
  • (C) 1.15
  • (D) 1.46

Question 28:

The electric field of a plane electromagnetic wave is given by
\( \overrightarrow E = {E_0}{{\widehat i + \widehat j} \over {\sqrt 2 }}\cos \left( {kz + \omega t} \right) \)

At t = 0, a positively charged particle is at the point (x, y, z) = \( \left( {0,0,{\pi \over k}} \right) \).
If its instantaneous velocity at (t = 0) is \( {v_0}\widehat k \) , the force acting on it due to the wave is :

  • (A) parallel to \( \widehat k \)
  • (B) parallel to \( {{\widehat i + \widehat j} \over {\sqrt 2 }} \)
  • (C) antiparallel to \( {{\widehat i + \widehat j} \over {\sqrt 2 }} \)
  • (D) zero

Question 29:

A mass of 10 kg is suspended by a rope of length 4 m, from the ceiling. A force F is applied horizontally at the mid point of the rope such that the top half of the rope makes an angle of 45o with the vertical. Then F equal : (Take g = 10 ms–2 and the rope to be massless)

  • (A) 100 N
  • (B) 75 N
  • (C) 90 N
  • (D) 70 N

Question 30:

In a Young's double slit experiment, the separation between the slits is 0.15 mm. in the experiment, a source of light of wavelengh 589 nm is used and the interference pattern is observed on a screen kept 1.5 m away. The separation between the successive bright fringes on the screen is :

  • (A) 4.9 mm
  • (B) 5.9 mm
  • (C) 6.9 mm
  • (D) 3.9 mm

Question 31:

A particle of mass m and charge q has an initial velocity \( \overrightarrow v = {v_0}\widehat j \) . If an electric field \( \overrightarrow E = {E_0}\widehat i \) and magnetic field \( \overrightarrow B = {B_0}\widehat i \) act on the particle, its speed will double after a time:

  • (A) \( {{3m{v_0}} \over {q{E_0}}} \)
  • (B) \( {{\sqrt 2 m{v_0}} \over {q{E_0}}} \)
  • (C) \( {{\sqrt 3 m{v_0}} \over {q{E_0}}} \)
  • (D) \( {{2m{v_0}} \over {q{E_0}}} \)

Question 32:

An electron (of mass m) and a photon have the same energy E in the range of a few eV. The ratio of the de-Broglie wavelength associated with the electron and the wavelength of the photon is (c = speed of light in vaccuum)

  • (A) \( {1 \over c}{\left( {{{2E} \over m}} \right)^{{1 \over 2}}} \)
  • (B) \( {1 \over c}{\left( {{E \over {2m}}} \right)^{{1 \over 2}}} \)
  • (C) \( {\left( {{E \over {2m}}} \right)^{{1 \over 2}}} \)
  • (D) \( c{\left( {2mE} \right)^{{1 \over 2}}} \)

Question 33:

A box weight 196 N on a spring balance at the north pole. Its weight recorded on the same balance if it is shifted to the equator is close to (Take g = 10 ms–2 at the north pole and the radius of the earth = 6400 km) :

  • (A) 194.32 N
  • (B) 195.66 N
  • (C) 195.32 N
  • (D) 194.66 N

Question 34:

The dimension of \( {{{B^2}} \over {2{\mu _0}}} \), where B is magnetic field and \( {{\mu _0}} \) is the magnetic permeability of vacuum, is :

  • (A) ML2T–2
  • (B) MLT–2
  • (C) ML-1T–2
  • (D) ML2T–1

Question 35:

An ideal fluid flows (laminar flow) through a pipe of non-uniform diameter. The maximum and minimum diameters of the pipes are \( 6.4\, cm \) and \( 4.8\, cm \), respectively. The ratio of the minimum and the maximum velocities of fluid in this pipe is :

  • (A) \( \frac{\sqrt{3}}{2} \)
  • (B) \( \frac{3}{4} \)
  • (C) \( \frac{81}{256} \)
  • (D) \( \frac{9}{16} \)

Question 36:

A planar loop of wire rotates in a uniform magnetic field. Initially at t = 0, the plane of the loop is perpendicular to the magnetic field. If it rotates with a period of 10 s about an axis in its plane then the magnitude of induced emf will be maximum and minimum, respectively at :

  • (A) 2.5 s and 7.5 s
  • (B) 5.0 s and 10.0 s
  • (C) 5.0 s and 7.5 s
  • (D) 2.5 s and 5.0 s

Question 37:

An elevator in a building can carry a maximum of 10 persons, with the average mass of each person being 68 kg, The mass of the elevator itself is 920 kg and it moves with a constant speed of 3 m/s. The frictional force opposing the motion is 6000 N. If the elevator is moving up with its full capacity, the power delivered by the motor to the elevator (g = 10 m/s2) must be at least :

  • (A) 48000 W
  • (B) 62360 W
  • (C) 56300 W
  • (D) 66000 W

Question 38:

A thin lens made of glass (refractive index = 1.5) of focal length f = 16 cm is immersed in a liquid of refractive index 1.42. If its focal length in liquid is f1 , then the ratio \( {{{f_1}} \over f} \) is closest to the integer :

  • (A) 17
  • (B) 1
  • (C) 9
  • (D) 5

Question 39:

In a building there are \( 15 \) bulbs of \( 45\, W, 15 \) bulbs of \( 100\, W \), \( 15 \) small fans of \( 10\, W \) and \( 2 \) heaters of \( 1\, kW \). The voltage of electric main is \( 220\, V \). The minimum fuse capacity (rated value) of the building will be:

  • (A) \( 25\, A \)
  • (B) \( 15\, A \)
  • (C) \( 10\, A \)
  • (D) \( 20\, A \)

Question 40:

In the figure, potential difference between A and B is :

  • (A) 10 V
  • (B) 5 V
  • (C) zero
  • (D) 15 V

Question 41:

Under an adiabatic process, the volume of an ideal gas gets doubled. Consequently the mean collision time between the gas molecule changes from \( {\tau _1} \) to \( {\tau _2} \) . If \( {{{C_p}} \over {{C_v}}} = \gamma \) for this gas then a good estimate for \( {{{\tau _2}} \over {{\tau _1}}} \) is given by :

  • (A) \( {\left( 2 \right)^{{{1 + \gamma } \over 2}}} \)
  • (B) 2
  • (C) \( {\left( {{1 \over 2}} \right)^{{{1 + \gamma } \over 2}}} \)
  • (D) \( {\left( {{1 \over 2}} \right)^\gamma } \)

Question 42:

The activity of a radioactive sample falls from \( 700\, s^{-1} \) to \( 500\, s^{-1} \) in 30 minutes. Its half life is close to :

  • (A) \( 72 \) min
  • (B) \( 62 \) min
  • (C) \( 66 \) min
  • (D) \( 52 \) min

Question 43:

Two ideal Carnot engines operate in cascade (all heat given up by one engine is used by the other engine to produce work) between temperature, T1 and T2 . The temperature of the hot reservoir of the first engine is T1 and the temperature of the cold reservoir of the second engine is T2 . T is temperature of the sink of first engine which is also the source for the second which is also the source for the second engine. How is T related to T1 and T2 . If both engines perform equal amount of work?

  • (A) \( T = {{2{T_1}{T_2}} \over {{T_1} + {T_2}}} \)
  • (B) \( T = \sqrt {{T_1}{T_2}} \)
  • (C) \( T = {{{T_1} + {T_2}} \over 2} \)
  • (D) T = 0

Question 44: The figure gives experimentally measured B vs H variation in a ferromagnetic material. The retentivity, coercivity and saturation, respectively, of the material are :
  • (A) 1.0 T, 50A/m and 1.5 T
  • (B) 1.5 T, 50 A/m and 1.0 T
  • (C) 1.5 T, 50 A/m and 2.0 T
  • (D) 150 A/m, 1.0 T and 1.5 T

Question 45:

A stationary observer receives sound from two identical tuning forks, one of which approaches and the other one recedes with the same speed (much less than the speed of sound). The observer hears 2 beats/sec. The oscillation frequency of each tuning fork is v0 = 1400 Hz and the velocity of sound in air is 350 m/s. The speed of each tuning fork is close to :

  • (A) 1 m/s
  • (B) \( {1 \over 8} \) m/s
  • (C) \( {1 \over 4} \) m/s
  • (D) \( {1 \over 2} \) m/s

Physics - Section B (Q46 - Q50)

Question 46:

The sum of two forces \( \overrightarrow P \) and \( \overrightarrow Q \) is \( \overrightarrow R \) such that \( \left| {\overrightarrow R } \right| = \left| {\overrightarrow P } \right| \) . The angle \( \theta \) (in degrees) that the resultant of 2\( {\overrightarrow P } \) and \( {\overrightarrow Q } \) will make with \( {\overrightarrow Q } \) is , ..............


Question 47: Consider a uniform cubical box of side a on a rough floor that is to be moved by applying minimum possible force F at a point b above its centre of mass (see figure). If the coefficient of friction is \( \mu \) = 0.4, the maximum possible value of 100 × \( {b \over a} \) for box not to topple before moving is .......

Question 48:

M grams of steam at 100oC is mixed with 200 g of ice at its melting point in a thermally insulated container. If it produced liquid water at 40oC [heat of vaporization of water is 540 cal/g and heat of fusion of ice is 80 cal/g] the value of M is ____


Question 49:

A 60 pF capacitor is fully charged by a 20 V supply. It is then disconnected from the supply and is conneced to another uncharged 60 pF capacitor in parallel. The electrostatic energy that is lost in this process by the time the charge is redistributed between them is (in nJ) _____


Question 50:

The balancing length for a cell is 560 cm in a potentiometer experiment. When an external resistance of 10 \( \Omega \) is connected in parallel to the cell, the balancing length changes by 60 cm. If the internal resistance of the ceil is \( {N \over {10}} \) \( \Omega \) , where N is an integer then value of N is .............


Chemistry - Section A (Q51 - Q70)

Question 51:

Among the statements(a)-(d) the incorrect ones are :
(a) Octahedral CO(III) complexes with strong fields ligands have very high magnetic moments.
(b) When \( \Delta \)0 < P, the d-electron configuration of Co(III) in an octahedral complex is \( t_{eg}^4e_g^2 \)
(c) Wavelength of light absorbed by [Co(en)3]3+ is lower than that of [CoF6]3-
(d) If the \( \Delta \)0 for an octahedral complex of CO(III) is 18,000 cm-1, the \( \Delta \)t for its tetrahedral complex with the same ligand be 16,000 cm-1

  • (A) (a) and (b) only
  • (B) (b) and (c) only
  • (C) (c) and (d) only
  • (D) (a) and (d) only

Question 52:

Within each pair of elements F & Cl, S & Se, and Li & Na, respectively, the elements that release more energy upon and electron gain are :

  • (A) F, S and Li
  • (B) Cl, Se and Na
  • (C) Cl, S and Li
  • (D) F, Se and Na

Question 53:

In the following reactions sequence, structure of A and B respectively will be :

  • (A)
  • (B)
  • (C)
  • (D)

Question 54:

Two open beakers one containing a solvent and the other containing a mixture of that solvent with a non volatile solute are together sealed in a container. Over time:

  • (A) the volume of the solution and the solvent does not change
  • (B) the volume of the solution increases and the volume of the solvent decreases
  • (C) the volume of the solution decreases and the volume of the solvent increases
  • (D) the volume of the solution does not change and the volume of the solvent decreases

Question 55:

The correct order of stability for the following alkoxides is :

  • (A) (C) > (B) > (A)
  • (B) (C) > (A) > (B)
  • (C) (B) > (C) > (A)
  • (D) (B) > (A) > (C)

Question 56:

The bond order and the magnetic characteristics of CN- are :

  • (A) 3, paramagnetic
  • (B) \( 2{1 \over 2} \), paramagnetic
  • (C) 3, diamagnetic
  • (D) \( 2{1 \over 2} \), diamagnetic

Question 57:

Which of the following statements is correct ?

  • (A) Gluconic acid can from cyclic (acteal/hemiacetal) structure
  • (B) Gluconic acid is a partial oxidation product of glucose
  • (C) Gluconic acid is obtained by oxidation of glucose with (HNO3)
  • (D) Gluconic acid is a dicarboxylic acid.

Question 58:

The number of possible optical isomers for the complexes MA2B2 with sp3 and dsp2 hydridized metal atom. respectively, is :
Note : A and B are unidentate netural and unidentate monoanionic ligands, respectively.

  • (A) 0 and 2
  • (B) 0 and 0
  • (C) 0 and 1
  • (D) 2 and 2

Question 59:

The redox reaction among the following is :

  • (A) reaction of H2SO4 with NaOH.
  • (B) formation of ozone form atmosphere oxygen in the presence of sunlight.
  • (C) combination of dinitrogen with dioxygen at 2000 K
  • (D) reaction of [Co(H2O)6]Cl3 With AgNO3

Question 60:

For the reaction
2H2(g) + 2NO(g) \( \to \) N2(g) + 2H2O(g)
the observed rate expression is, rate = Kf[NO]2[H2]. The rate expression for the reverse reaction is :

  • (A) Kb[N2][H2O]
  • (B) Kb[N2][H2O]2/[H2]
  • (C) Kb[N2][H2O]2/[NO]
  • (D) Kb[N2][H2O]2

Question 61:

Consider the following reactions :
Which of these reactions are possible ?

  • (A) (b), (c) and (d)
  • (B) (a) and (b)
  • (C) (a) and (d)
  • (D) (b) and (d)

Question 62:

The equation that is incorrect is :

  • (A) \( {\left( {\Lambda _m^0} \right)_{KCl}} - {\left( {\Lambda _m^0} \right)_{NaCl}} = {\left( {\Lambda _m^0} \right)_{KBr}} - {\left( {\Lambda _m^0} \right)_{NaBr}} \)
  • (B) \( {\left( {\Lambda _m^0} \right)_{NaBr}} - {\left( {\Lambda _m^0} \right)_{NaI}} = {\left( {\Lambda _m^0} \right)_{KBr}} - {\left( {\Lambda _m^0} \right)_{NaBr}} \)
  • (C) \( {\left( {\Lambda _m^0} \right)_{NaBr}} - {\left( {\Lambda _m^0} \right)_{NaCl}} = {\left( {\Lambda _m^0} \right)_{KBr}} - {\left( {\Lambda _m^0} \right)_{KCl}} \)
  • (D) \( {\left( {\Lambda _m^0} \right)_{{H_2}O}} = {\left( {\Lambda _m^0} \right)_{HCl}} + {\left( {\Lambda _m^0} \right)_{NaOH}} - {\left( {\Lambda _m^0} \right)_{NaCl}} \)

Question 63:

For the following reactions


Ks and Ke, are respectively, the rate constants for substitution and elimination and \( \mu = {{{k_s}} \over {{k_e}}} \) the correct options is

  • (A) \( {\mu _B} > {\mu _A} \) and Ke(A) > Ke(B)
  • (B) \( {\mu _A} > {\mu _B} \) and Ke(B) > Ke(A)
  • (C) \( {\mu _B} > {\mu _A} \) and Ke(B) > Ke(A)
  • (D) \( {\mu _A} > {\mu _B} \) and Ke(A) > Ke(B)

Question 64:

A chromatography column, packed with silica gel as stationary phase, was used to separate a mixture of compounds consisting of (A) benzanilide (B) aniline and (C) acetophenone. When the column is eluted with a mixture of solvents, hexane : ethylacelate (20:80), the sequence of obtained compounds is :

  • (A) (A), (B) and (C)
  • (B) (B), (A) and (C)
  • (C) (C), (A) and (B)
  • (D) (B), (C) and (A)

Question 65:

In the following reaction sequence,


The major product B is :

  • (A)
  • (B)
  • (C)
  • (D)

Question 66:

The ammonia (NH3) released on quantitative reaction of 0.6 g urea (NH2CONH2) with sodium hydroxide (NaOH) can be neutralized by :

  • (A) 200 ml of 0.02 N HCl
  • (B) 100 ml of 0.2 N HCl
  • (C) 100 ml of 0.1 HCl
  • (D) 200 ml of 0.4 N HCl

Question 67:

In the following reaction, products (A) and (B) respectively, are :

NaOH + Cl2 \( \to \) (A) + side products
(hot and conc.)

Ca(OH)2 + Cl2 \( \to \) (B) + side products (dry)

  • (A) NaOCl and Ca(OCl)2
  • (B) NaClO3 and Ca(ClO3)2
  • (C) NaOCl and Ca(ClO3)2
  • (D) NaClO3 and Ca(OCl)2

Question 68:

Among statements (a)-(d), the correct ones are: (a) Decomposition of hydrogen peroxide gives dioxygen. (b) Like hydrogen peroxide,compounds, such as \( KClO_3, Pb (NO_3)_2 \) and \( NaNO_3 \) when heated liberate dioxygen. (c) 2-Ethylanthraquinone is useful for the industrial preparation of hydrogen peroxide. (d) Hydrogen peroxide is used for the manufacture of sodium perborate.

  • (A) (a), (b), (c) and (d)
  • (B) (a), (b) and (c) only
  • (C) (a), (c) and (d) only
  • (D) (a) and (c) only Question

Question 69:

Identify the correct labels of A,B and C in the following graph from the options given below :


Root mean square speed (Vrms); most probable speed (Vmp); Average speed (Vav)

  • (A) A - Vav ; B - Vrms ; C - Vmp
  • (B) A - Vrms ; B - Vmp ; C - Vav
  • (C) A - Vmp; B- Vav; C - Vrms
  • (D) A - Vmp ; B - Vrms ; C - Vav

Question 70:

The refining method used when the metal and the impurities have low and high melting temperatures, respectively, is :

  • (A) liquation
  • (B) vapour phase refining
  • (C) distillation
  • (D) zone refining

Chemistry - Section B (Q71 - Q75)

Question 71:

The flocculation value of HCl for arsenic sulphide sol.
is 30 m mol L-1 If H2SO4 is used for the flocculatiopn of arsenic sulphide, the amount in grams, of H2SO4 in 250 ml required for the above purposed is ______.
(molecular mass of H2SO4 = 98 g/mol)


Question 72:

The standard heat of formation \( \left( {{\Delta _f}H_{298}^0} \right) \) of ethane (in kj/mol), if the heat of combustion of ethane, hydrogen and graphite are - 1560, -393.5 and -286 Kj/mol, respectively is :


Question 73:

3 g of acetic acid is added to 250 mL of 0.1 M HCL and the solution made up to 500 mL. To 20 mL of this solutions \( {1 \over 2} \) mL of 5 M NaOH is added. The pH of the solution is __________.

[Given : pKa of acetic acid = 4.75, molar mass of acetic of acid = 60 g/mol, log 3 = 0.4771] Neglect any changes in volume.


Question 74:

Consider the following reactions :

\( NaCl{\rm{ }} + {\rm{ }}{K_2}C{r_2}{O_7} + \mathop {{H_2}S{O_4}}\limits_{(conc.)} \)\( \to \) (A) + side products

(A) + NaOH \( \to \) (B) + Side products

\( \left( B \right){\rm{ }} + \mathop {{H_2}S{O_4}}\limits_{(dilute)} + {\rm{ }}{H_2}{O_2} \) \( \to \) (C) + Side products

The sum of the total number of atoms in one molecule each of (A) and (B) and (C) is


Question 75:

The number of sp2 hybridised carbons present in "Aspartame" is

JEE Main 2020 Exam Pattern and Marking Scheme

ParticularsDetails
Exam ModeOnline (Computer-Based Test)
PaperB.E./B.Tech (Paper 1)
Duration3 hours (180 minutes)
Type of QuestionsMultiple Choice Questions (MCQs) + Numerical Value Questions
SubjectsMathematics, Physics, Chemistry
Total Questions75 questions
Total Marks300 marks
Marking Scheme+4 for correct answer & -1 for incorrect MCQ; no negative marking for Numerical Value-based Questions

JEE Main 2020 January 7 Shift 2 Paper Analysis