JEE Main 2021 (Online) 16th March Evening Shift
JEE Main / 90 questions
2026Tue, Mar 16, 2021 9:30 AM90 PYQs
1Alcohols Phenols And Ethers
The structure of X is :
MCQ+4 / -12021
2Aldehydes Ketones And Carboxylic Acids
In the above reaction, the reagent ''A'' is :
MCQ+4 / -12021
3Biomolecules
The secondary structure of protein is stabilised by:
MCQ+4 / -12021
4Chemical Kinetics And Nuclear Chemistry
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 _________ m...
INTEGER+4 / -12021
5Compounds Containing Nitrogen
Ammonolysis of Alkyl halides followed by the treatment with NaOH solution can be used to prepare primary, secondary and tertiary amines. The purpose of NaOH in the reaction is :
MCQ+4 / -12021
6Compounds Containing Nitrogen
Which of the following is least basic?
MCQ+4 / -12021
7Coordination Compounds
[Ti(H2O)6]3+ absorbs light of wavelength 498 nm during a d \(-\) d transition. The octahedral splitting energy for the above complex is ____________ \(\times\) 10\(-\)19 J. (Round off to the Nearest Integer). h = 6.626 \(\times\) 10\(-\)34 ...
INTEGER+4 / -12021
8D And F Block Elements
Fex2 and Fey3 are known when x and y are :
MCQ+4 / -12021
9D And F Block Elements
Arrange the following metal complex/compounds in the increasing order of spin only magnetic moment. Presume all the three, high spin system.(Atomic numbers Ce = 58, Gd = 64 and Eu = 63)(a) (NH4)2[Ce(NO3)6](b) Gd(NO3)3 and (c) Eu(NO3)3
MCQ+4 / -12021
10Electrochemistry
A 5.0 m mol dm\(-\)3 aqueous solution of KCl has a conductance of 0.55 mS when measured in a cell of cell constant 1.3 cm\(-\)1. The molar conductivity of this solution is ___________ mSm2 mol\(-\)1. (Round off to the Nearest Integer).
INTEGER+4 / -12021
11Environmental Chemistry
The green house gas/es is (are) :(A) Carbon dioxide(B) Oxygen(C) Water vapour(D) MethaneChoose the most appropriate answer from the options given below :
MCQ+4 / -12021
12Haloalkanes And Haloarenes
Identify the reagent(s) 'A' and condition(s) for the reaction
MCQ+4 / -12021
13Hydrocarbons
An unsaturated hydrocarbon X on ozonolysis gives A. Compound A when warmed with ammonical silver nitrate forms a bright silver mirror along the sides of the test tube. The unsaturated hydrocarbon X is :
MCQ+4 / -12021
14Hydrogen
The correct statements about H2O2 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 option...
MCQ+4 / -12021
15Ionic Equilibrium
Sulphurous acid (H2SO3) has Ka1 = 1.7 \(\times\) 10\(-\)2 and Ka2 = 6.4 \(\times\) 10\(-\)8. The pH of 0.588 M H2SO3 is __________. (Round off to the Nearest Integer).
INTEGER+4 / -12021
16Isolation Of Elements
Which of the following reduction reaction CANNOT be carried out with coke?
MCQ+4 / -12021
17P Block Elements
The INCORRECT statement regarding the structure of C60 is :
MCQ+4 / -12021
18Periodic Table And Periodicity
The characteristics of elements X, Y and Z with atomic numbers, respectively, 33, 53 and 83 are :
MCQ+4 / -12021
19Periodic Table And Periodicity
Identify the elements X and Y using the ionisation energy values given below :
Ionization energy (kJ/mol)
1\({st}\)
2\({nd}\)
X
495
4563
Y
731
1450
Ionization energy (kJ/mol)
1\({st}\)
2\({nd}\)
X
495
4563
Y
731
1450
MCQ+4 / -12021
20Polymers
Which of the following polymer is used in the manufacture of wood laminates?
MCQ+4 / -12021
21Practical Organic Chemistry
Match List - I with List - II :
List - I Test/Reagents/Observation(s)
List - II Species detected
(a)
Lassaigne's Test
(i)
Carbon
(b)
Cu(II) oxide
(ii)
Sulphur
(c)...
List - I Test/Reagents/Observation(s)
List - II Species detected
(a)
Lassaigne's Test
(i)
Carbon
(b)
Cu(II) oxide
(ii)
Sulphur
(c)...
MCQ+4 / -12021
22Practical Organic Chemistry
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+4 / -12021
23Redox Reactions
Statement I : Sodium hydride can be used as an oxidising agent.Statement II : The lone pair of electrons on nitrogen in pyridine makes it basic.Choose the CORRECT answer from the options given below :
MCQ+4 / -12021
24Solid State
Ga (atomic mass 70 u) crystallizes in a hexagonal close packed structure. The total number of voids in 0.581 g of Ga is __________ \(\times\) 1021. (Round off to the Nearest Integer). [Given : NA = 6.023 \(\times\) 1023]
INTEGER+4 / -12021
25Solutions
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).
INTEGER+4 / -12021
26Some Basic Concepts Of Chemistry
The exact volumes of 1 M NaOH solution required to neutralise 50 mL of 1 M H3PO3 solution and 100 mL of 2 M H3PO2 solution, respectively, are :
MCQ+4 / -12021
27Some Basic Concepts Of Chemistry
When 35 mL of 0.15 M lead nitrate solution is mixed with 20 mL of 0.12 M chromic sulphate solution, _________ \(\times\) 10\(-\)5 moles of lead sulphate precipitate out. (Round off to the Nearest Integer).
INTEGER+4 / -12021
28Structure Of Atom
The number of orbitals with n = 5, m1 = +2 is ___________. (Round off to the Nearest Integer).
INTEGER+4 / -12021
29Surface Chemistry
The INCORRECT statements below regarding colloidal solutions is :
MCQ+4 / -12021
30Thermodynamics
At 25\(^\circ\)C, 50 g of iron reacts with HCl to form FeCl2. 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 : ...
INTEGER+4 / -12021
313d Geometry
If the foot of the perpendicular from point (4, 3, 8) on the line \({L_1}:{{x - a} \over l} = {{y - 2} \over 3} = {{z - b} \over 4}\), l \(\ne\) 0 is (3, 5, 7), then the shortest distance between the line L1 and line $${L_2}:{{x - 2} \over ...
MCQ+4 / -12021
323d Geometry
If (x, y, z) be an arbitrary point lying on a plane P which passes through the points (42, 0, 0), (0, 42, 0) and (0, 0, 42), then the value of the expression $$3 + {{x - 11} \over {{{(y - 19)}^2}{{(z - 12)}^2}}} + {{y - 19} \over {{{(x - 11...
MCQ+4 / -12021
333d Geometry
If the distance of the point (1, \(-\)2, 3) from the plane x + 2y \(-\) 3z + 10 = 0 measured parallel to the line, \({{x - 1} \over 3} = {{2 - y} \over m} = {{z + 3} \over 1}\) is \(\sqrt {{7 \over 2}}\), then the value of |m| is equal to ...
INTEGER+4 / -12021
34Application Of Derivatives
The maximum value of \(f(x) = \left| {\matrix{
{{{\sin }^2}x} & {1 + {{\cos }^2}x} & {\cos 2x} \cr
{1 + {{\sin }^2}x} & {{{\cos }^2}x} & {\cos 2x} \cr
{{{\sin }^2}x} & {{{\cos }^2}x} & {\sin 2x} \cr
} } \right|,x \in R\) is...
MCQ+4 / -12021
35Application Of Derivatives
Let f be a real valued function, defined on R \(-\) {\(-\)1, 1} and given by f(x) = 3 loge \(\left| {{{x - 1} \over {x + 1}}} \right| - {2 \over {x - 1}}\).Then in which of the following intervals, function f(x) is increasing?
MCQ+4 / -12021
36Binomial Theorem
Let n be a positive integer. Let $$A = \sum\limits_{k = 0}^n {{{( - 1)}^k}{}^n{C_k}\left[ {{{\left( {{1 \over 2}} \right)}^k} + {{\left( {{3 \over 4}} \right)}^k} + {{\left( {{7 \over 8}} \right)}^k} + {{\left( {{{15} \over {16}}} \right)}^...
INTEGER+4 / -12021
37Circle
Let the lengths of intercepts on x-axis and y-axis made by the circle x2 + y2 + ax + 2ay + c = 0, (a < 0) be 2\({\sqrt 2 }\) and 2\({\sqrt 5 }\), respectively. Then the shortest distance from origin to a tangent to this circle which is perp...
MCQ+4 / -12021
38Complex Numbers
The least value of |z| where z is complex number which satisfies the inequality \(\exp \left( {{{(|z| + 3)(|z| - 1)} \over {||z| + 1|}}{{\log }_e}2} \right) \ge {\log _{\sqrt 2 }}|5\sqrt 7 + 9i|,i = \sqrt { - 1}\), is equal to :
MCQ+4 / -12021
39Definite Integration
Consider the integral \(I = \int_0^{10} {{{[x]{e^{[x]}}} \over {{e^{x - 1}}}}dx}\), where [x] denotes the greatest integer less than or equal to x. Then the value of I is equal to :
MCQ+4 / -12021
40Definite Integration
Let P(x) = x2 + bx + c be a quadratic polynomial with real coefficients such that \(\int_0^1 {P(x)dx}\) = 1 and P(x) leaves remainder 5 when it is divided by (x \(-\) 2). Then the value of 9(b + c) is equal to :
MCQ+4 / -12021
41Differential Equations
Let C1 be the curve obtained by the solution of differential equation \(2xy{{dy} \over {dx}} = {y^2} - {x^2},x > 0\). Let the curve C2 be the solution of \({{2xy} \over {{x^2} - {y^2}}} = {{dy} \over {dx}}\). If both the curves pass through...
MCQ+4 / -12021
42Differential Equations
If y = y(x) is the solution of the differential equation \({{dy} \over {dx}}\) + (tan x) y = sin x, \(0 \le x \le {\pi \over 3}\), with y(0) = 0, then \(y\left( {{\pi \over 4}} \right)\) equal to :
MCQ+4 / -12021
43Ellipse
If the points of intersections of the ellipse \({{{x^2}} \over {16}} + {{{y^2}} \over {{b^2}}} = 1\) and the circle x2 + y2 = 4b, b > 4 lie on the curve y2 = 3x2, then b is equal to :
MCQ+4 / -12021
44Indefinite Integrals
For real numbers \(\alpha\), \(\beta\), \(\gamma\) and \(\delta\), if \(\int {{{({x^2} - 1) + {{\tan }^{ - 1}}\left( {{{{x^2} + 1} \over x}} \right)} \over {({x^4} + 3{x^2} + 1){{\tan }^{ - 1}}\left( {{{{x^2} + 1} \over x}} \right)}}dx}\)...
INTEGER+4 / -12021
45Inverse Trigonometric Functions
Given that the inverse trigonometric functions take principal values only. Then, the number of real values of x which satisfy $${\sin ^{ - 1}}\left( {{{3x} \over 5}} \right) + {\sin ^{ - 1}}\left( {{{4x} \over 5}} \right) = {\sin ^{ - 1}}x$...
MCQ+4 / -12021
46Limits Continuity And Differentiability
Let f : S \(\to\) S where S = (0, \(\infty\)) be a twice differentiable function such that f(x + 1) = xf(x). If g : S \(\to\) R be defined as g(x) = loge f(x), then the value of |g''(5) \(-\) g''(1)| is equal to :
MCQ+4 / -12021
47Limits Continuity And Differentiability
Let \(\alpha\) \(\in\) R be such that the function $$f(x) = \left\{ {\matrix{
{{{{{\cos }^{ - 1}}(1 - {{\{ x\} }^2}){{\sin }^{ - 1}}(1 - \{ x\} )} \over {\{ x\} - {{\{ x\} }^3}}},} & {x \ne 0} \cr
{\alpha ,} & {x = 0} \cr
} } \...
{{{{{\cos }^{ - 1}}(1 - {{\{ x\} }^2}){{\sin }^{ - 1}}(1 - \{ x\} )} \over {\{ x\} - {{\{ x\} }^3}}},} & {x \ne 0} \cr
{\alpha ,} & {x = 0} \cr
} } \...
MCQ+4 / -12021
48Limits Continuity And Differentiability
Let f : R \(\to\) R and g : R \(\to\) R be defined as \(f(x) = \left\{ {\matrix{
{x + a,} & {x < 0} \cr
{|x - 1|,} & {x \ge 0} \cr
} } \right.\) and $$g(x) = \left\{ {\matrix{
{x + 1,} & {x < 0} \cr
{{{(x - 1)}^2} + ...
{x + 1,} & {x < 0} \cr
{{{(x - 1)}^2} + ...
INTEGER+4 / -12021
49Matrices And Determinants
Let \(A = \left[ {\matrix{
{{a_1}} \cr
{{a_2}} \cr
} } \right]\) and \(B = \left[ {\matrix{
{{b_1}} \cr
{{b_2}} \cr
} } \right]\) be two 2 \(\times\) 1 matrices with real entries such that A = XB, where $$X = {1 \ove...
INTEGER+4 / -12021
50Parabola
Let C be the locus of the mirror image of a point on the parabola y2 = 4x with respect to the line y = x. Then the equation of tangent to C at P(2, 1) is :
MCQ+4 / -12021
