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JEE Advanced 2021 Paper 1 Online

JEE Advanced / 57 questions

2026Sun, Oct 3, 2021 3:30 AM57 PYQs
1Aldehydes Ketones And Carboxylic Acids
In the reaction given below, the total number of atoms having sp2 hybridization in the major product P is _________.
INTEGER+4 / -02021
2Basics Of Organic Chemistry
Among the following, the conformation that corresponds to the most stable conformation of meso-butane-2,3-diol is
MCQ+3 / -12021
3Basics Of Organic Chemistry
The maximum number of possible isomers (including stereoisomers) which may be formed on mono-bromination of 1-methylcyclohex-1-ene using Br2 and UV light is ___________.
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4Biomolecules
Given : The compound(s), which on reaction with HNO3 will give the product having degree of rotation, [\(\alpha\)]D = \(-\)52.7\(^\circ\) is (are)
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5Compounds Containing Nitrogen
The reaction of Q with PhSNa yields an organic compound (major product) that gives positive Carius test on treatment with Na2O2 followed by addition of BaCl2. The correct option(s) for Q is (are)
MCQM+4 / -22021
6Coordination Compounds
The calculated spin only magnetic moments of [
Cr(NH3)6]3+ and [CuF6]3\(-\) in BM, respectively, are(Atomic numbers of Cr and Cu are 24 and 29, respectively)
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7Coordination Compounds
The total number of possible isomers for [Pt(NH3)4Cl2]Br2 is ______.
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8Hydrocarbons
The major product formed in the following reaction of
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9Hydrocarbons
For the following reaction scheme, percentage yields are given along the arrow:x g and y g are mass of R and U, respectively.(Use : Molar mass (in g mol\(-\)1) of H, C and O as 1, 12 and 16, respectively)The value of x is ________.
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10Hydrocarbons
The value of y is ________.
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11Isolation Of Elements
The correct statement(s) related to the metal extraction processes is (are) :
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12Isolation Of Elements
A mixture of two salts is used to prepare a solution S, which gives the following results :The correct option(s) for the salt mixture is (are)
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13Solid State
For the given close packed structure of a salt made of cation X and anion Y shown below (ions of only one face are shown for clarity), the packing fraction is approximately (packing fraction = \({{packing\,efficiency} \over {100}}\))
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14Solutions
The value of x is ________.
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15Solutions
The value of | y | is ________.
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16Surface Chemistry
The correct statement(s) related to colloids is (are)
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17Thermodynamics
The value of standard enthalpy, \(\Delta\)Ho (in kJ mol\(-\)1) for the given reaction is _______.
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18Thermodynamics
The value of \(\Delta\)S\(\theta\) (in J K\(-\)1 mol\(-\)1) for the given reaction, at 1000 K is _________.
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19Thermodynamics
An ideal gas undergoes a reversible isothermal expansion from state I to state II followed by a reversible adiabatic expansion from state II to state III. The correct plot(s) representing the changes from state I to state III is (are)(p : p...
MCQM+4 / -22021
20Application Of Integration
The area of the region \(\left\{ {\matrix{ {(x,y):0 \le x \le {9 \over 4},} & {0 \le y \le 1,} & {x \ge 3y,} & {x + y \ge 2} \cr } } \right\}\) is
MCQ+3 / -12021
21Circle
Consider a triangle \(\Delta\) whose two sides lie on the x-axis and the line x + y + 1 = 0. If the orthocenter of \(\Delta\) is (1, 1), then the equation of the circle passing through the vertices of the triangle \(\Delta\) is
MCQ+3 / -12021
22Complex Numbers
Let $\theta_1, \theta_2, \ldots, \theta_{10}$ be positive valued angles (in radian) such that $\theta_1+\theta_2+\cdots+\theta_{10}=2 \pi$. Define the complex numbers $z_1=e^{i \theta_1}, z_k=z_{k-1} e^{i \theta_k}$ for $k=2,3, \ldots, 10$,...
MCQ+3 / -12021
23Complex Numbers
For any complex number w = c + id, let \(\arg (w) \in ( - \pi ,\pi ]\), where \(i = \sqrt { - 1}\). Let \(\alpha\) and \(\beta\) be real numbers such that for all complex numbers z = x + iy satisfying $$\arg \left( {{{z + \alpha } \over {z...
MCQM+4 / -22021
24Limits Continuity And Differentiability
Let f : R \(\to\) R be defined by \(f(x) = {{{x^2} - 3x - 6} \over {{x^2} + 2x + 4}}\)Then which of the following statements is (are) TRUE?
MCQM+4 / -22021
25Matrices And Determinants
Let \(\alpha\), \(\beta\) and \(\gamma\) be real numbers such that the system of linear equationsx + 2y + 3z = \(\alpha\)4x + 5y + 6z = \(\beta\)7x + 8y + 9z = \(\gamma\) \(-\) 1is consistent. Let | M | represent the determinant of the mat...
INTEGER+2 / -02021
26Matrices And Determinants
Let \(\alpha\), \(\beta\) and \(\gamma\) be real numbers such that the system of linear equationsx + 2y + 3z = \(\alpha\)4x + 5y + 6z = \(\beta\)7x + 8y + 9z = \(\gamma\) \(-\) 1is consistent. Let | M | represent the determinant of the mat...
INTEGER+2 / -02021
27Matrices And Determinants
For any 3 \(\times\) 3 matrix M, let | M | denote the determinant of M. Let\(E = \left[ {\matrix{ 1 & 2 & 3 \cr 2 & 3 & 4 \cr 8 & {13} & {18} \cr } } \right]\), $$P = \left[ {\matrix{
1 & 0 & 0 \cr
0 & 0 & 1 \cr
...
MCQM+4 / -22021
28Matrices And Determinants
For any 3 \(\times\) 3 matrix M, let |M| denote the determinant of M. Let I be the 3 \(\times\) 3 identity matrix. Let E and F be two 3 \(\times\) 3 matrices such that (I \(-\) EF) is invertible. If G = (I \(-\) EF)\(-\)1, then which of the...
MCQM+4 / -22021
29Probability
Consider three sets E1 = {1, 2, 3}, F1 = {1, 3, 4} and G1 = {2, 3, 4, 5}. Two elements are chosen at random, without replacement, from the set E1, and let S1 denote the set of these chosen elements. Let E2 = E1 \(-\) S1 and F2 = F1 \(\cup\)...
MCQ+3 / -12021
30Probability
Three numbers are chosen at random, one after another with replacement, from the set S = {1, 2, 3, ......, 100}. Let p1 be the probability that the maximum of chosen numbers is at least 81 and p2 be the probability that the minimum of chose...
INTEGER+2 / -02021
31Probability
Three numbers are chosen at random, one after another with replacement, from the set S = {1, 2, 3, ......, 100}. Let p1 be the probability that the maximum of chosen numbers is at least 81 and p2 be the probability that the minimum of chose...
INTEGER+2 / -02021
32Probability
Let E, F and G be three events having probabilities \(P(E) = {1 \over 8}\), \(P(F) = {1 \over 6}\) and \(P(G) = {1 \over 4}\), and let P (E \(\cap\) F \(\cap\) G) = \({1 \over {10}}\). For any event H, if Hc denotes the complement, then whi...
MCQM+4 / -22021
33Properties Of Triangle
In a triangle ABC, let AB = \(\sqrt {23}\), BC = 3 and CA = 4. Then the value of \({{\cot A + \cot C} \over {\cot B}}\) is _________.
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34Quadratic Equation And Inequalities
For x \(\in\) R, the number of real roots of the equation \(3{x^2} - 4\left| {{x^2} - 1} \right| + x - 1 = 0\) is ________.
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35Sequences And Series
For any positive integer n, let Sn : (0, \(\infty\)) \(\to\) R be defined by \({S_n}(x) = \sum\nolimits_{k = 1}^n {{{\cot }^{ - 1}}\left( {{{1 + k(k + 1){x^2}} \over x}} \right)}\), where for any x \(\in\) R, $${\cot ^{ - 1}}(x) \in (0,\pi...
MCQM+4 / -22021
36Straight Lines And Pair Of Straight Lines
Consider the lines L1 and L2 defined by \({L_1}:x\sqrt 2 + y - 1 = 0\) and \({L_2}:x\sqrt 2 - y + 1 = 0\)For a fixed constant \(\lambda\), let C be the locus of a point P such that the product of the distance of P from L1 and the distance...
INTEGER+2 / -02021
37Straight Lines And Pair Of Straight Lines
Consider the lines L1 and L2 defined by \({L_1}:x\sqrt 2 + y - 1 = 0\) and \({L_2}:x\sqrt 2 - y + 1 = 0\)For a fixed constant \(\lambda\), let C be the locus of a point P such that the product of the distance of P from L1 and the distance...
INTEGER+2 / -02021
38Vector Algebra
Let \(\overrightarrow u\), \(\overrightarrow v\) and \(\overrightarrow w\) be vectors in three-dimensional space, where \(\overrightarrow u\) and \(\overrightarrow v\) are unit vectors which are not perpendicular to each other and $$\o...
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39Atoms And Nuclei
A heavy nucleus Q of half-life 20 minutes undergoes alpha-decay with probability of 60% and beta-decay with probability of 40%. Initially, the number of Q nuclei is 1000. The number of alpha-decays of Q in the first one hour is
MCQ+3 / -12021
40Atoms And Nuclei
Which of the following statement(s) is(are) correct about the spectrum of the hydrogen atom?
MCQM+4 / -22021
41Capacitor
In the circuit shown below, the switch S is connected to position P for a long time so that the charge on the capacitor becomes q1 \(\mu\)C. Then S is switched to position Q. After a long time, the charge on the capacitor is q2 \(\mu\)C.The...
INTEGER+2 / -02021
42Capacitor
In the circuit shown below, the switch S is connected to position P for a long time so that the charge on the capacitor becomes q1 \(\mu\)C. Then S is switched to position Q. After a long time, the charge on the capacitor is q2 \(\mu\)C.The...
INTEGER+2 / -02021
43Electrostatics
Two point charges \(-\)Q and +Q/\(\sqrt 3\) are placed in the xy-plane at the origin (0, 0) and a point (2, 0), respectively, as shown in the figure. This results in an equipotential circle of radius R and potential V = 0 in the xy-plane w...
INTEGER+2 / -02021
44Electrostatics
Two point charges \(-\)Q and +Q/\(\sqrt 3\) are placed in the xy-plane at the origin (0, 0) and a point (2, 0), respectively, as shown in the figure. This results in an equipotential circle of radius R and potential V = 0 in the xy-plane w...
INTEGER+2 / -02021
45Geometrical Optics
An extended object is placed at point O, 10 cm in front of a convex lens L1 and a concave lens L2 is placed 10 cm behind it, as shown in the figure. The radii of curvature of all the curved surfaces in both the lenses ae 20 cm. The refracti...
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46Geometrical Optics
A wide slab consisting of two media of refractive indices n1 and n2 is placed in air as shown in the figure. A ray of light is incident from medium n1 to n2 at an angle \(\theta\), where sin\(\theta\) is slightly larger than 1/n1. Take refr...
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47Heat And Thermodynamics
An ideal gas undergoes a four step cycle as shown in the P-V diagram below. During this cycle, heat is absorbed by the gas in
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48Heat And Thermodynamics
A small object is placed at the center of a large evacuated hollow spherical container. Assume that the container is maintained at 0 K. At time t = 0, the temperature of the object is 200 K. The temperature of the object becomes 100 K at t ...
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49Impulse And Momentum
A particle of mass M = 0.2 kg is initially at rest in the xy-plane at a point (x = \(-\)l, y = \(-\)h), where l = 10 m and h = 1 m. The particle is accelerated at time t = 0 with a constant acceleration a = 10 m/s2 along the positive x-dire...
MCQM+4 / -22021
50Laws Of Motion
A projectile is thrown from a point O on the ground at an angle 45\(^\circ\) from the vertical and with a speed 5\(\sqrt 2\) m/s. The projectile at the highest point of its trajectory splits into two equal parts. One part falls vertically ...
INTEGER+2 / -02021

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