JEE Main 2020 (Online) 5th September Evening Slot
Paper was held on
Sat, Sep 5, 2020 9:30 AM
Chemistry
1
The increasing order of boiling points of the following compounds is :


2
Lattice enthalpy and enthalpy of solution of NaCl are 788 kJ mol–1, and 4 kJ mol–1, respectively.
The hydration enthalpy of NaCl is :
The hydration enthalpy of NaCl is :
3
The rate constant (k) of a reaction is measured at differenct temperatures (T), and the data are
plotted in the given figure. The activation energy of the reaction in kJ mol–1 is :
(R is gas constant)
(R is gas constant)

4
The compound that has the largest H–M–H bond angle (M = N, O, S, C) is :
5
Considering that $$\Delta $$0
> P, the magnetic moment
(in BM) of [Ru(H2O)6]2+ would be _________.
(in BM) of [Ru(H2O)6]2+ would be _________.
6
The correct order of the ionic radii of
O2–, N3–, F– , Mg2+, Na+ and Al3+ is :
O2–, N3–, F– , Mg2+, Na+ and Al3+ is :
7
Consider the complex ions,
trans-[Co(en)2Cl2]+ (A) and
cis-[Co(en)2Cl2]+ (B).
The correct statement regarding them is :
trans-[Co(en)2Cl2]+ (A) and
cis-[Co(en)2Cl2]+ (B).
The correct statement regarding them is :
8
For a reaction X + Y ⇌ 2Z , 1.0 mol of X, 1.5 mol
of Y and 0.5 mol of Z were taken in a 1 L vessel and
allowed to react. At equilibrium, the concentration
of Z was 1.0 mol L–1. The equilibrium constant of reaction
is $${x \over {15}}$$. The value of x is _________.
of Y and 0.5 mol of Z were taken in a 1 L vessel and
allowed to react. At equilibrium, the concentration
of Z was 1.0 mol L–1. The equilibrium constant of reaction
is $${x \over {15}}$$. The value of x is _________.
9
For a dimerization reaction,
2A(g) $$ \to $$ A2(g)
at 298 K, $$\Delta $$Uo = –20 kJ mol–1, $$\Delta $$So = –30 JK–1 mol–1,
then the $$\Delta $$Go will be _____ J.
2A(g) $$ \to $$ A2(g)
at 298 K, $$\Delta $$Uo = –20 kJ mol–1, $$\Delta $$So = –30 JK–1 mol–1,
then the $$\Delta $$Go will be _____ J.
10
Among the following compounds, geometrical isomerism is exhibited by :
11
The number of chiral carbons present in
sucrose is _____.
12
The volume, in mL, of 0.02 M K2Cr2O7 solution
required to react with 0.288 g of ferrous
oxalate in acidic medium is _______.
(Molar mass of Fe = 56 g mol–1)
(Molar mass of Fe = 56 g mol–1)
13
The final major product of the following reaction is :


14
Boron and silicon of very high purity can be obtained through :
15
The correct statement about probability density (except at infinite distance from nucleus) is :
16
The major product of the following reaction is :


17
The variation of molar conductivity with concentration of an electrolyte (X) in aqueous solution
is shown in the given figure.
The electrolyte X is :
The electrolyte X is :
18
The major product formed in the following reaction is :
CH3CH = CHCH(CH3)2 $$\buildrel {HBr} \over \longrightarrow $$
CH3CH = CHCH(CH3)2 $$\buildrel {HBr} \over \longrightarrow $$
Mathematics
1
The value of $${\left( {{{ - 1 + i\sqrt 3 } \over {1 - i}}} \right)^{30}}$$ is :
2
If the mean and the standard deviation of the
data 3, 5, 7, a, b are 5 and 2 respectively, then a and b are the roots of the equation :
data 3, 5, 7, a, b are 5 and 2 respectively, then a and b are the roots of the equation :
3
If L = sin2$$\left( {{\pi \over {16}}} \right)$$ - sin2$$\left( {{\pi \over {8}}} \right)$$ and
M = cos2$$\left( {{\pi \over {16}}} \right)$$ - sin2$$\left( {{\pi \over {8}}} \right)$$, then :
M = cos2$$\left( {{\pi \over {16}}} \right)$$ - sin2$$\left( {{\pi \over {8}}} \right)$$, then :
4
$$\mathop {\lim }\limits_{x \to 0} {{x\left( {{e^{\left( {\sqrt {1 + {x^2} + {x^4}} - 1} \right)/x}} - 1} \right)} \over {\sqrt {1 + {x^2} + {x^4}} - 1}}$$
5
If the sum of the second, third and fourth terms
of a positive term G.P. is 3 and the sum of its
sixth, seventh and eighth terms is 243, then the
sum of the first 50 terms of this G.P. is :
6
The derivative of
$${\tan ^{ - 1}}\left( {{{\sqrt {1 + {x^2}} - 1} \over x}} \right)$$ with
respect to $${\tan ^{ - 1}}\left( {{{2x\sqrt {1 - {x^2}} } \over {1 - 2{x^2}}}} \right)$$ at x = $${1 \over 2}$$ is :
$${\tan ^{ - 1}}\left( {{{\sqrt {1 + {x^2}} - 1} \over x}} \right)$$ with
respect to $${\tan ^{ - 1}}\left( {{{2x\sqrt {1 - {x^2}} } \over {1 - 2{x^2}}}} \right)$$ at x = $${1 \over 2}$$ is :
7
There are 3 sections in a question paper and
each section contains 5 questions. A candidate
has to answer a total of 5 questions, choosing
at least one question from each section. Then
the number of ways, in which the candidate
can choose the questions, is :
8
If
$$\int {{{\cos \theta } \over {5 + 7\sin \theta - 2{{\cos }^2}\theta }}} d\theta $$ = A$${\log _e}\left| {B\left( \theta \right)} \right| + C$$,
where C is a constant of integration, then $${{{B\left( \theta \right)} \over A}}$$
can be :
$$\int {{{\cos \theta } \over {5 + 7\sin \theta - 2{{\cos }^2}\theta }}} d\theta $$ = A$${\log _e}\left| {B\left( \theta \right)} \right| + C$$,
where C is a constant of integration, then $${{{B\left( \theta \right)} \over A}}$$
can be :
9
If the length of the chord of the circle,
x2 + y2 = r2 (r > 0) along the line, y – 2x = 3 is r,
then r2 is equal to :
x2 + y2 = r2 (r > 0) along the line, y – 2x = 3 is r,
then r2 is equal to :
10
If x = 1 is a critical point of the function
f(x) = (3x2 + ax – 2 – a)ex , then :
f(x) = (3x2 + ax – 2 – a)ex , then :
11
The area (in sq. units) of the region
A = {(x, y) : (x – 1)[x] $$ \le $$ y $$ \le $$ 2$$\sqrt x $$, 0 $$ \le $$ x $$ \le $$ 2}, where [t]
denotes the greatest integer function, is :
A = {(x, y) : (x – 1)[x] $$ \le $$ y $$ \le $$ 2$$\sqrt x $$, 0 $$ \le $$ x $$ \le $$ 2}, where [t]
denotes the greatest integer function, is :
12
Let y = y(x) be the solution of the differential
equation
cosx$${{dy} \over {dx}}$$ + 2ysinx = sin2x, x $$ \in $$ $$\left( {0,{\pi \over 2}} \right)$$.
If y$$\left( {{\pi \over 3}} \right)$$ = 0, then y$$\left( {{\pi \over 4}} \right)$$ is equal to :
cosx$${{dy} \over {dx}}$$ + 2ysinx = sin2x, x $$ \in $$ $$\left( {0,{\pi \over 2}} \right)$$.
If y$$\left( {{\pi \over 3}} \right)$$ = 0, then y$$\left( {{\pi \over 4}} \right)$$ is equal to :
13
Let the vectors $$\overrightarrow a $$, $$\overrightarrow b $$, $$\overrightarrow c $$
be such that
$$\left| {\overrightarrow a } \right| = 2$$, $$\left| {\overrightarrow b } \right| = 4$$ and $$\left| {\overrightarrow c } \right| = 4$$. If the projection of
$$\overrightarrow b $$ on $$\overrightarrow a $$ is equal to the projection of $$\overrightarrow c $$ on $$\overrightarrow a $$
and $$\overrightarrow b $$ is perpendicular to $$\overrightarrow c $$, then the value of
$$\left| {\overrightarrow a + \vec b - \overrightarrow c } \right|$$ is ___________.
$$\left| {\overrightarrow a } \right| = 2$$, $$\left| {\overrightarrow b } \right| = 4$$ and $$\left| {\overrightarrow c } \right| = 4$$. If the projection of
$$\overrightarrow b $$ on $$\overrightarrow a $$ is equal to the projection of $$\overrightarrow c $$ on $$\overrightarrow a $$
and $$\overrightarrow b $$ is perpendicular to $$\overrightarrow c $$, then the value of
$$\left| {\overrightarrow a + \vec b - \overrightarrow c } \right|$$ is ___________.
14
If $$\alpha $$ and $$\beta $$ are the roots of the equation,
7x2 – 3x – 2 = 0, then the value of
$${\alpha \over {1 - {\alpha ^2}}} + {\beta \over {1 - {\beta ^2}}}$$ is equal to :
7x2 – 3x – 2 = 0, then the value of
$${\alpha \over {1 - {\alpha ^2}}} + {\beta \over {1 - {\beta ^2}}}$$ is equal to :
15
If the system of linear equations
x + y + 3z = 0
x + 3y + k2z = 0
3x + y + 3z = 0
has a non-zero solution (x, y, z) for some k $$ \in $$ R, then x + $$\left( {{y \over z}} \right)$$ is equal to :
x + y + 3z = 0
x + 3y + k2z = 0
3x + y + 3z = 0
has a non-zero solution (x, y, z) for some k $$ \in $$ R, then x + $$\left( {{y \over z}} \right)$$ is equal to :
16
Let A = {a, b, c} and B = {1, 2, 3, 4}. Then the
number of elements in the set
C = {f : A $$ \to $$ B | 2 $$ \in $$ f(A) and f is not one-one} is ______.
C = {f : A $$ \to $$ B | 2 $$ \in $$ f(A) and f is not one-one} is ______.
17
If a + x = b + y = c + z + 1, where a, b, c, x, y, z
are non-zero distinct real numbers, then
$$\left| {\matrix{ x & {a + y} & {x + a} \cr y & {b + y} & {y + b} \cr z & {c + y} & {z + c} \cr } } \right|$$ is equal to :
are non-zero distinct real numbers, then
$$\left| {\matrix{ x & {a + y} & {x + a} \cr y & {b + y} & {y + b} \cr z & {c + y} & {z + c} \cr } } \right|$$ is equal to :
Physics
1
A ring is hung on a nail. It can oscillate, without
slipping or sliding
(i) in its plane with a time period T1 and,
(ii) back and forth in a direction perpendicular to its plane,
with a period T2. The ratio $${{{T_1}} \over {{T_2}}}$$ will be :
(i) in its plane with a time period T1 and,
(ii) back and forth in a direction perpendicular to its plane,
with a period T2. The ratio $${{{T_1}} \over {{T_2}}}$$ will be :
2
An infinitely long, straight wire carrying current
I, one side opened rectangular loop and a
conductor C with a sliding connector are
located in the same plane, as shown, in the
figure. The connector has length $$l$$ and
resistance R. It slides to the right with a
velocity v. The resistance of the conductor and
the self inductance of the loop are negligible.
The induced current in the loop, as a function
of separation r, between the connector and the
straight wire is :


3
An iron rod of volume 10–3 m3 and relative
permeability 1000 is placed as core in a
solenoid with 10 turns/cm. If a current of 0.5 A
is passed through the solenoid, then the
magnetic moment of the rod will be :
4
In an experiment to verify Stokes law, a small
spherical ball of radius r and density $$\rho $$ falls
under gravity through a distance h in air before
entering a tank of water. If the terminal velocity
of the ball inside water is same as its velocity
just before entering the water surface, then the
value of h is proportional to :
(ignore viscosity of air)
(ignore viscosity of air)
5
A spaceship in space sweeps stationary
interplanetary dust. As a result, its mass
increases at a rate $${{dM\left( t \right)} \over {dt}}$$ = bv2(t), where v(t) is its instantaneous velocity. The instantaneous acceleration of the satellite is :
increases at a rate $${{dM\left( t \right)} \over {dt}}$$ = bv2(t), where v(t) is its instantaneous velocity. The instantaneous acceleration of the satellite is :
6
In an adiabatic process, the density of a
diatomic gas becomes 32 times its initial value.
The final pressure of the gas is found to be n
times the initial pressure. The value of n is :
7
The quantities x = $${1 \over {\sqrt {{\mu _0}{\varepsilon _0}} }}$$, y = $${E \over B}$$ and z = $${l \over {CR}}$$ are
defined where C-capacitance, R-Resistance, l-length, E-Electric field, B-magnetic field and $${{\varepsilon _0}}$$, $${{\mu _0}}$$, - free space permittivity and permeability respectively. Then :
defined where C-capacitance, R-Resistance, l-length, E-Electric field, B-magnetic field and $${{\varepsilon _0}}$$, $${{\mu _0}}$$, - free space permittivity and permeability respectively. Then :
8
A body of mass 2 kg is driven by an engine
delivering a constant power of 1 J/s. The body
starts from rest and moves in a straight line.
After 9 seconds, the body has moved a
distance (in m) _______.
9
Two different wires having lengths L1 and L2,
and respective temperature coefficient of linear
expansion $$\alpha $$1 and $$\alpha $$2, are joined end-to-end.
Then the effective temperature coefficient of
linear expansion is :
10
The correct match between the entries in
column I and column II are :
| I | II |
|---|---|
| Radiation | Wavelength |
| (a) Microwave | (i) 100 m |
| (b) Gamma rays | (ii) 10–15 m |
| (c) A.M. radio waves | (iii) 10–10 m |
| (d) X-rays | (iv) 10–3 m |
11
The surface of a metal is illuminated alternately
with photons of energies E1 = 4 eV and E2 = 2.5 eV
respectively. The ratio of maximum speeds of the
photoelectrons emitted in the two cases is 2. The
work function of the metal in (eV) is _____.
12
Two coherent sources of sound, S1 and S2,
produce sound waves of the same wavelength,
$$\lambda $$ = 1 m, in phase. S1 and S2 are placed 1.5 m
apart (see fig). A listener, located at L, directly
in front of S2 finds that the intensity is at a
minimum
when he is 2 m away from S2. The listener moves away from S1, keeping his distance from S2 fixed. The adjacent maximum of intensity is observed when the listener is at a distance d from S1. Then, d is :
when he is 2 m away from S2. The listener moves away from S1, keeping his distance from S2 fixed. The adjacent maximum of intensity is observed when the listener is at a distance d from S1. Then, d is :

13
The acceleration due to gravity on the earth’s
surface at the poles is g and angular velocity of
the earth about the axis passing through the
pole is $$\omega $$. An object is weighed at the equator
and at a height h above the poles by using a
spring balance. If the weights are found to be
same, then h is (h << R, where R is the radius
of the earth)
14
In the circuit shown, charge on the 5 $$\mu $$F
capacitor is :


15
Ten charges are placed on the circumference
of a circle of radius R with constant angular
separation between successive charges.
Alternate charges 1, 3, 5, 7, 9 have charge (+q)
each, while 2, 4, 6, 8, 10 have charge (–q) each.
The potential V and the electric field E at the
centre of the circle are respectively.
(Take V = 0 at infinity)
(Take V = 0 at infinity)
16
Nitrogen gas is at 300oC temperature. The
temperature (in K) at which the rms speed of a
H2 molecule would be equal to the rms speed
of a nitrogen molecule, is _______.
(Molar mass of N2 gas 28 g).
(Molar mass of N2 gas 28 g).
17
A galvanometer is used in laboratory for
detecting the null point in electrical
experiments. If, on passing a current of 6 mA it
produces a deflection of 2o, its figure of merit
is close to :
18
In the circuit, given in the figure currents in
different branches and value of one resistor are
shown. Then potential at point B with respect to
the point A is :


19
A prism of angle A = 1o has a refractive index
$$\mu $$ = 1.5. A good estimate for the minimum angle
of deviation (in degrees) is close to $${N \over {10}}$$.
Value of N is ____.
Value of N is ____.
20
The velocity (v) and time (t) graph of a body in
a straight line motion is shown in the figure.
The point S is at 4.333 seconds. The total
distance covered by the body in 6 s is :


21
A parallel plate capacitor has plate of length
'l', width ‘w’ and separation of plates is ‘d’. It
is connected to a battery of emf V. A dielectric
slab of the same thickness ‘d’ and of dielectric
constant k = 4 is being inserted between the
plates of the capacitor. At what length of the
slab inside plates, will the energy stored in the
capacitor be two times the initial energy
stored?
22
Two Zener diodes (A and B) having breakdown
voltages of 6 V and 4 V respectively, are
connected as shown in the circuit below. The
output voltage V0 variation with input voltage
linearly increasing with time, is given by :
(Vinput = 0 V at t = 0)
(figures are qualitative)
(Vinput = 0 V at t = 0)
(figures are qualitative)

23
A thin rod of mass 0.9 kg and length 1 m is
suspended, at rest, from one end so that it can
freely oscillate in the vertical plane. A particle
of move 0.1 kg moving in a straight line with
velocity 80 m/s hits the rod at its bottom most
point and sticks to it (see figure). The angular
speed (in rad/s) of the rod immediately after the
collision will be _________.

