JEE Main 2020 (Online) 9th January Evening Slot

Paper was held on
Thu, Jan 9, 2020 9:30 AM

## Chemistry

The first and second ionisation enthalpies of a
metal are 496 and 4560 kJ mol–1, respectively.
How many moles of HCl and

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A mixture of gases O2, H2 and CO are taken in
a closed vessel containing charcoal. The graph
that represents the correct

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Which of the following reactions will not
produce a racemic product?

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In the following reaction A is :

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Which polymer has 'chiral' monomer(s) ?

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Among the statements (a)-(d) the correct ones
are :
(a) Lithium has the highest hydration enthalpy
among the alkali meta

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Biochemical Oxygen Demand (BOD) is the
amount of oxygen required (in ppm) :

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The correct order of the spin-only magnetic
moments of the following complexes is :
(I) [Cr(H2O)6]Br2
(II) Na4[Fe(CN)6]

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Amongst the following, the form of water with
the lowest ionic conductance at 298 K is :

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Which of the following has the shortest C-Cl
bond?

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In the figure shown below reactant A
(represented by square) is in equilibrium with
product B (represented by circle). T

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The decreasing order of basicity of the
following amines is :

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The solubility product of Cr(OH)3 at 298 K is
6.0 × 10–31. The concentration of hydroxide ions
in a saturated solution o

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5 g of zinc is treated separately with an excess
of
(a) dilute hydrochloric acid and
(b) aqueous sodium hydroxide.
The r

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Consider the following reactions,
The compound [P] is :

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A, B and C are three biomolecules. The results
of the tests performed on them are given
below:
$$
\begin{array}{|l|l|l|l

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The reaction of H3N3B3Cl3 (A) with LiBH4 in
tetrahydrofuran gives inorganic benzene (B).
Further, the reaction of (A) wi

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The isomer(s) of [Co(NH3)4Cl2] that has/have
a Cl–Co–Cl angle of 90°, is/are :

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The number of sp2 hybrid orbitals in a molecule
of benzene is :

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The true statement amongst the following is :

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A cylinder containing an ideal gas (0.1 mol of
1.0 dm3) is in thermal equilibrium with a large
volume of 0.5 molal aqueo

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A sample of milk splits after 60 min. at 300 K
and after 40 min. at 400 K when the population
of lactobacillus acidophil

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The sum of the total number of bonds between
chromium and oxygen atoms in chromate and
dichromate ions is ____________.

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10.30 mg of O2 is dissolved into a liter of sea
water of density 1.03 g/mL. The concentration
of O2 in ppm is__________.

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Consider the following reactions
The mass percentage of carbon in A is ______.

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## Mathematics

Let [t] denote the greatest integer $$ \le $$ t
and $$\mathop {\lim }\limits_{x \to 0} x\left[ {{4 \over x}} \right] = A

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The following system of linear equations
7x + 6y – 2z = 0
3x + 4y + 2z = 0
x – 2y – 6z = 0, has

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Let a, b $$ \in $$ R, a $$ \ne $$ 0 be such that the equation,
ax2 – 2bx + 5 = 0 has a repeated root $$\alpha $$, which

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A random variable X has the following
probability distribution :
.tg {border-collapse:collapse;border-spacing:0;width:

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If $$x = 2\sin \theta - \sin 2\theta $$ and $$y = 2\cos \theta - \cos 2\theta $$,
$$\theta \in \left[ {0,2\pi } \righ

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The length of the minor axis (along y-axis) of
an ellipse in the standard form is $${4 \over {\sqrt 3 }}$$. If this
elli

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Given : $$f(x) = \left\{ {\matrix{
{x\,\,\,\,\,,} & {0 \le x < {1 \over 2}} \cr
{{1 \over 2}\,\,\,\,,} &a

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If $$x = \sum\limits_{n = 0}^\infty {{{\left( { - 1} \right)}^n}{{\tan }^{2n}}\theta } $$ and $$y = \sum\limits_{n = 0

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If A = {x $$ \in $$ R : |x| < 2} and B = {x $$ \in $$ R : |x – 2| $$ \ge $$ 3};
then :

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If 10 different balls are to be placed in 4 distinct
boxes at random, then the probability that two
of these boxes conta

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If one end of a focal chord AB of the parabola
y2 = 8x is at $$A\left( {{1 \over 2}, - 2} \right)$$, then the equation o

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Let a function ƒ : [0, 5] $$ \to $$ R be continuous,
ƒ(1) = 3 and F be defined as :
$$F(x) = \int\limits_1^x {{t^2}g(t)d

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If $${{dy} \over {dx}} = {{xy} \over {{x^2} + {y^2}}}$$; y(1) = 1; then a value of x
satisfying y(x) = e is :

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If $$\int {{{d\theta } \over {{{\cos }^2}\theta \left( {\tan 2\theta + \sec 2\theta } \right)}}} = \lambda \tan \theta

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If p $$ \to $$ (p $$ \wedge $$ ~q) is false, then the truth values
of p and q are respectively :

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If z be a complex number satisfying
|Re(z)| + |Im(z)| = 4, then |z| cannot be :

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Let a – 2b + c = 1.
If $$f(x)=\left| {\matrix{
{x + a} & {x + 2} & {x + 1} \cr
{x + b} & {x + 3} &am

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In the expansion of $${\left( {{x \over {\cos \theta }} + {1 \over {x\sin \theta }}} \right)^{16}}$$, if $${\ell _1}$$ i

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The number of terms common to the two A.P.'s
3, 7, 11, ....., 407 and 2, 9, 16, ....., 709 is ______.

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Let $$\overrightarrow a $$, $$\overrightarrow b $$ and $$\overrightarrow c $$ be three vectors such that $$\left| {\over

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Let an be the nth term of a G.P. of positive terms.
$$\sum\limits_{n = 1}^{100} {{a_{2n + 1}} = 200} $$ and $$\sum\limit

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Let ƒ and g be differentiable functions on R
such that fog is the identity function. If for some
a, b $$ \in $$ R, g'(a)

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If the distance between the plane,
23x – 10y – 2z + 48 = 0 and the plane
containing the lines
$${{x + 1} \over 2} = {{y

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If Cr $$ \equiv $$ 25Cr and
C0 + 5.C1 + 9.C2 + .... + (101).C25 = 225.k, then k is equal to _____.

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If the curves, x2 – 6x + y2 + 8 = 0 and
x2 – 8y + y2 + 16 – k = 0, (k > 0) touch each other
at a point, then the larg

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## Physics

A wire of length L and mass per unit length
6.0 × 10–3 kgm–1 is put under tension of
540 N. Two consecutive frequencies

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A spring mass system (mass m, spring
constant k and natural length $$l$$) rest in
equilibrium on a horizontal disc. The

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A rod of length L has non-uniform linear mass
density given by $$\rho $$(x) = $$a + b{\left( {{x \over L}} \right)^2}$$

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An electron gun is placed inside a long solenoid
of radius R on its axis. The solenoid has n
turns/length and carries a

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A plane electromagnetic wave is propagating
along the direction
$${{\widehat i + \widehat j} \over {\sqrt 2 }}$$
, with

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A small spherical droplet of density d is floating
exactly half immersed in a liquid of density $$\rho $$
and surface te

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A small circular loop of conducting wire has
radius a and carries current I. It is placed in a
uniform magnetic field B

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The current i in the network is :

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In LC circuit the inductance L = 40 mH and
capacitance C = 100 $$\mu $$F. If a voltage
V(t) = 10sin(314t) is applied to

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There is a small source of light at some depth
below the surface of water (refractive
index = $${4 \over 3}$$) in a tank

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Two gases-argon (atomic radius 0.07 nm,
atomic weight 40) and xenon (atomic radius
0.1 nm, atomic weight 140) have the s

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A particle of mass m is projected with a speed
u from the ground at an angle
$$\theta = {\pi \over 3}$$ w.r.t.
horizon

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A particle starts from the origin at t = 0 with an
initial velocity of 3.0 $$\widehat i$$ m/s and moves in the
x-y plane

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The energy required to ionise a hydrogen like
ion in its ground state is 9 Rydbergs. What is
the wavelength of the radia

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Two identical capacitors A and B, charged to
the same potential 5V are connected in two
different circuits as shown belo

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A uniformly thick wheel with moment of inertia
I and radius R is free to rotate about its centre
of mass (see fig). A ma

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Planet A has mass M and radius R. Planet B has
half the mass and half the radius of Planet A.
If the escape velocities f

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For the four sets of three measured physical
quantities as given below. Which of the
following options is correct ?
(i)

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Two steel wires having same length are
suspended from a ceiling under the same load.
If the ratio of their energy stored

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An electron of mass m and magnitude of charge
|e| initially at rest gets accelerated by a constant
electric field E. The

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Starting at temperature 300 K, one mole of an
ideal diatomic gas ($$\gamma $$ = 1.4) is first compressed
adiabatically f

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In a meter bridge experiment S is a standard
resistance. R is a resistance wire. It is found
that balancing length is $$

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The circuit shown below is working as a 8 V
dc regulated voltage source. When 12 V is used
as input, the power dissipate

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In a Young's double slit experiment 15 fringes
are observed on a small portion of the screen
when light of wavelength 50

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An electric field $$\overrightarrow E = 4x\widehat i - \left( {{y^2} + 1} \right)\widehat j$$ N/C
passes through the bo

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