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JEE Main 2021 20th July Evening Shift

Browse the complete Chemistry, Mathematics, and Physics question set from the JEE Main 2021 20th July Evening Shift paper, question by question. Each question shows a quick preview so you can jump straight to the topic or subject you want to revise. Click through to attempt the full question in practice mode, or head back to the paper-wise list to download the entire shift as a PDF.

This paper has 90 questions in total - 38 easy (42%), 34 moderate (38%) and 18 tough (20%). That's an easier-than-usual mix for this exam - aim to clear it quickly and save time for the harder papers. By subject: Physics 50% easy, 40% moderate, 10% tough; Chemistry 40% easy, 33% moderate, 27% tough; Mathematics 37% easy, 40% moderate, 23% tough.

Chemistry questions were spread across 22 chapters, with General Organic Chemistry (3), Structure of Atom (3), and Amines (2) carrying the most weight. Mathematics questions were spread across 22 chapters, with Definite Integration (3), Sequences and Series (3), and Differential Equations (2) carrying the most weight. Physics questions were spread across 21 chapters, with Rotational Motion (3), Alternating Current (2), and Dual Nature of Matter (2) carrying the most weight.

Chemistry

  1. 1Which one of the following pairs of isomers is an example of metamerism?20 Jul, 2021 (E)Isomerism of Organic Compounds
  2. 2In the above reactions, product A and product B respectively are:20 Jul, 2021 (E)Preparation and Properties of Amides
  3. 3The major product (P) in the following reaction is:20 Jul, 2021 (E)Chemical reactions for aldehydes and ketones
  4. 4The single largest industrial application of dihydrogen is:20 Jul, 2021 (E)Chemical properties of hydrogen
  5. 5Consider two chemical reactions (A) and (B) that take place during metallurgical process: (A) ZnCO 3 s ZnO s + CO 2 g (B) 2 ZnS s + 3 O 2 g 20 Jul, 2021 (E)Concentration of the Ore
  6. 6A solution is 0 . 1 M in Cl - and 0 . 001 M in CrO 4 2 - . Solid AgNO 3 is gradually added to it Assuming that the addition does not change 20 Jul, 2021 (E)Solubility
  7. 7Outermost electronic configuration of a group 13 element, E , is 4 s 2 , 4 p 1 . The electronic configuration of an element of p-block perio20 Jul, 2021 (E)Electronic configuration
  8. 8Metallic sodium does not react normally with:20 Jul, 2021 (E)General Characteristics of Alkali Metals
  9. 9Spin only magnetic moment of an octahedral complex of Fe 2 + in the presence of a strong field ligand in BM is:20 Jul, 2021 (E)Werner's theory and Valence Bond Theory
  10. 10Which one of the following species doesn t have a magnetic moment of 1 . 73 BM , (spin only value)?20 Jul, 2021 (E)Quantum mechanical model
  11. 11Which one of the following statements is not true about enzymes?20 Jul, 2021 (E)Enzymes and Receptors
  12. 12The hybridisations of the atomic orbitals of nitrogen in NO 2 - , NO 2 + and NH 4 + respectively are.20 Jul, 2021 (E)Hybridisation and VSEPR Theory
  13. 13Bakelite is a cross-linked polymer of formaldehyde and:20 Jul, 2021 (E)Classification of Polymers
  14. 14Benzene on nitration gives nitrobenzene in presence of HNO 3 and H 2 SO 4 mixture, where:20 Jul, 2021 (E)Reactions of aromatic compounds
  15. 15Consider the above reaction, compound B is:20 Jul, 2021 (E)Preparation and Properties of Amines
  16. 16Major product P of above reaction, is:20 Jul, 2021 (E)Reactions of alkenes
  17. 17Cu 2 + salt reacts with potassium iodide to give20 Jul, 2021 (E)Oxidation and Reduction Reactions
  18. 18In Carius method, halogen containing organic compound is heated with fuming nitric acid in the presence of:20 Jul, 2021 (E)Quantitative analysis of organic compounds
  19. 19Which one of the following gases is reported to retard photosynthesis?20 Jul, 2021 (E)Environmental Pollution and pollutants
  20. 20The correct order of their reactivity towards hydrolysis at room temperature is:20 Jul, 2021 (E)Preparation and Properties of Acid Derivatives
  21. 21For a given chemical reaction A B at 300 K the free energy change is - 49 . 4 kJ mol - 1 and the enthalpy of reaction is 51 . 4 kJ mol - 1 .20 Jul, 2021 (E)Entropy and Second law of thermodynamics
  22. 22The wavelength of electrons accelerated from rest through a potential difference of 40 kV is X 10 - 12 m . The value of x is. (Nearest integ20 Jul, 2021 (E)Dual Behaviour of Matter and Heisenberg Uncertainty Principle
  23. 23The vapour pressures of A and B at 25 C are 90 mmHg and 15 mm Hg respectively. If A and B are mixed such that the mole fraction of A in the 20 Jul, 2021 (E)Vapour pressure and raoult's law
  24. 244 g equimolar mixture of NaOH and Na 2 CO 3 contains xg of NaOH and yg of Na 2 CO 3 . The value of x is g . (Nearest integer)20 Jul, 2021 (E)Equivalence concept
  25. 25When 0 . 15 g of an organic compound was analyzed using Carius method for estimation of bromine, 0 . 2397 g of AgBr was obtained. The percen20 Jul, 2021 (E)Quantitative analysis of organic compounds
  26. 26For coagulation of 50 mL of a sol, 10 mL of 0.5M Cl - ion solution is required. What is the coagulating value of Cl - ion solution (Nearest 20 Jul, 2021 (E)Properties of colloidal solution
  27. 27PCl 5 g PCl 3 g + Cl 2 g In the above first order reaction the concentration of PCl 5 reduces from initial concentration 50 mol L - 1 to 10 20 Jul, 2021 (E)Rate law and rate constant
  28. 28Diamond has a three dimensional structure of C atoms formed by covalent bonds. The structure of diamond has face centred cubic lattice where20 Jul, 2021 (E)Cubic system
  29. 29An aqueous solution of NiCl 2 was heated with excess sodium cyanide in presence of strong oxidizing agent to form Ni ( CN ) 6 2 - . The tota20 Jul, 2021 (E)Werner's theory and Valence Bond Theory
  30. 30Potassium chlorate is prepared by electrolysis of KCl in basic solution as shown by following equation. 6 OH - + Cl - ClO 3 - + 3 H 2 O + 6 20 Jul, 2021 (E)Cells and Electrode Potential, Nernst Equation

Mathematics

  1. 1For the natural numbers m , n , if ( 1 - y ) m ( 1 + y ) n = 1 + a 1 y + a 2 y 2 + . + a m + n y m + n and a 1 = a 2 = 10 , then the value o20 Jul, 2021 (E)Terms of Binomial Expansion
  2. 2The value of tan 2 tan - 1 3 5 + sin - 1 5 13 is equal to:20 Jul, 2021 (E)Sum and difference of angles
  3. 3Let r 1 and r 2 be the radii of the largest and smallest circles, respectively, which pass through the point ( - 4 , 1 ) and having their ce20 Jul, 2021 (E)Equation of Circle & its intercept
  4. 4Consider the following three statements: A If 3 + 3 = 7 then 4 + 3 = 8 B If 5 + 3 = 8 then earth is flat. C If both A and B are true then 5 20 Jul, 2021 (E)Mathematical Reasoning
  5. 5The lines x = a y - 1 = z - 2 and x = 3 y - 2 = b z - 2 , ( a b 0 ) are coplanar, if:20 Jul, 2021 (E)Line in Space
  6. 6If [ x ] denotes the greatest integer less than or equal to x , then the value of the integral - / 2 / 2 x - sin x d x is equal to:20 Jul, 2021 (E)Properties of Definite Integration
  7. 7If the real part of the complex number 1 - cos + 2 i sin - 1 is 1 5 for ( 0 , ) , then the value of the integral 0 sin x d x is equal to:20 Jul, 2021 (E)Euler Form and De Moivres Theorem
  8. 8Let f : R - 6 R be defined by f x = 5 x + 3 6 x - . Then the value of for which f o f x = x , for all x R - 6 , is20 Jul, 2021 (E)Composite Function
  9. 9If f : R R is given by f ( x ) = x + 1 , then the value of lim n 1 n f 0 + f 5 n + f 10 n + . . + f 5 ( n - 1 ) n is:20 Jul, 2021 (E)Definite as Limit of Sum
  10. 10Let A , B and C be three events such that the probability that exactly one of A and B occurs is ( 1 - k ) , the probability that exactly one20 Jul, 2021 (E)Addition and Subtraction Theorems
  11. 11The sum of all the local minimum values of the twice differentiable function f : R R defined by f x = x 3 - 3 x 2 - 3 f ( 2 ) 2 x + f 1 is:20 Jul, 2021 (E)Maxima Minima
  12. 12Let in a right angled triangle, the smallest angle be . If a triangle formed by taking the reciprocal of its sides is also a right angled tr20 Jul, 2021 (E)Sine Rule and its application
  13. 13Let y = y ( x ) satisfies the equation d y d x - A = 0 , for all x 0 , where A = y sin x 1 0 - 1 1 2 0 1 x . If y ( ) = + 2 , then the value20 Jul, 2021 (E)Linear Differential Equation
  14. 14Consider the line L given by the equation x - 3 2 = y - 1 1 = z - 2 1 . Let Q be the mirror image of the point ( 2 , 3 , - 1 ) with respect 20 Jul, 2021 (E)Plane in Space
  15. 15If the mean and variance of six observations 7 , 10 , 11 , 15 , a , b are 10 and 20 3 , respectively, then the value of | a - b | is equal t20 Jul, 2021 (E)Measures of Dispersion
  16. 16Let g t = - / 2 / 2 cos 4 t + f x d x , where f x = log e x + x 2 + 1 , x R . Then which one of the following is correct?20 Jul, 2021 (E)Properties of Definite Integration
  17. 17Let P be a variable point on the parabola y = 4 x 2 + 1 . Then, the locus of the mid-point of the point P and the foot of the perpendicular 20 Jul, 2021 (E)Locus
  18. 18The value of k R , for which the following system of linear equations 3 x - y + 4 z = 3 x + 2 y - 3 z = - 2 6 x + 5 y + k z = - 3 has infini20 Jul, 2021 (E)System of Linear Equations
  19. 19If sum of the first 21 terms of the series log 9 1 / 2 x + log 9 1 / 3 x + log 9 1 / 4 x + . . where x 0 is 504 , then x is equal to20 Jul, 2021 (E)Arithmetic Progression
  20. 20In a triangle A B C , if | B C | = 3 , | C A | = 5 and | B A | = 7 , then the projection of the vector B A on B C is equal to20 Jul, 2021 (E)Product of 2 vectors
  21. 21Let A = a i j be a 3 3 matrix, where a i j = - 1 j - i if i j 2 if i = j - 1 i + j if i j then det 3 Adj 2 A - 1 is equal to ________.20 Jul, 2021 (E)Adjoint and its Properties
  22. 22Let a curve y = y x be given by the solution of the differential equation cos 1 2 cos - 1 e - x d x = e 2 x - 1 d y . If it intersects y -ax20 Jul, 2021 (E)Variable Separable Form
  23. 23For p 0 , a vector v 2 = 2 i ^ + p + 1 j ^ is obtained by rotating the vector v 1 = 3 p i ^ + j ^ by an angle about origin in counter clockw20 Jul, 2021 (E)Product of 2 vectors
  24. 24Consider a triangle having vertices A ( - 2 , 3 ) , B ( 1 , 9 ) and C ( 3 , 8 ) . If a line L passing through the circum-centre of triangle 20 Jul, 2021 (E)Coordinate System
  25. 25If the point on the curve y 2 = 6 x , nearest to the point 3 , 3 2 is ( , ) , then 2 ( + ) is equal to _________.20 Jul, 2021 (E)Normal to Parabola
  26. 26Let a function g : 0 , 4 R be defined as g x = max t 3 - 6 t 2 + 9 t - 3 0 t x , 0 x 3 4 - x , 3 x 4 then the number of points in the interv20 Jul, 2021 (E)Differentiability
  27. 27Let a n n = 1 be a sequence such that a 1 = 1 , a 2 = 1 and a n + 2 = 2 a n + 1 + a n for all n 1 . Then the value of 47 n = 1 a n 2 3 n is 20 Jul, 2021 (E)Summation of Series
  28. 28If lim x 0 x e x - log e ( 1 + x ) + x 2 e - x x sin 2 x = 10 , , , R , then the value of + + is __________.20 Jul, 2021 (E)Miscellaneous
  29. 29The number of solutions of the equation log ( x + 1 ) 2 x 2 + 7 x + 5 + log ( 2 x + 5 ) ( x + 1 ) 2 - 4 = 0 , x 0 , is20 Jul, 2021 (E)Logarithm
  30. 30For k N , let 1 ( + 1 ) ( + 2 ) . ( + 20 ) = K = 0 20 A k + k , where 0 . Then the value of 100 A 14 + A 15 A 13 2 is equal to ____________.20 Jul, 2021 (E)Summation of Series

Physics

  1. 1If the kinetic energy of a moving body becomes four times its initial kinetic energy, then the percentage change in its momentum will be:20 Jul, 2021 (E)Energy
  2. 2A boy reaches the airport and finds that the escalator is not working. He walks up the stationary escalator in time t 1 . If he remains stat20 Jul, 2021 (E)Relative motion
  3. 3A satellite is launched into a circular orbit of radius R around earth, while a second satellite is launched into a circular orbit of radius20 Jul, 2021 (E)Kepler laws
  4. 4With what speed should a galaxy move outward with respect to earth so that the sodium- D line at wavelength 5890 A is observed at 5896 A ?20 Jul, 2021 (E)Doppler's Effect
  5. 5The length of a metal wire is 1 , when the tension in it is T 1 and is 2 when the tension is T 2 . The natural length of the wire is:20 Jul, 2021 (E)Young's Modulus and Breaking Stres
  6. 6In an electromagnetic wave, the electric field vector and magnetic field vector are given as E = E 0 i ^ and B = B 0 k ^ , respectively. The20 Jul, 2021 (E)Electromagnetic Waves and Maxwell's equations
  7. 7For a series LCR circuit with R = 100 , L = 0 . 5 mH and C = 0 . 1 pF connected across 220 V - 50 Hz AC supply, the phase angle between curr20 Jul, 2021 (E)AC Circuits
  8. 8Which of the following graphs represent the behaviour of an ideal gas? Symbols have their usual meaning.20 Jul, 2021 (E)Thermodynamic Processes
  9. 9A particle is making simple harmonic motion along the X -axis. If at a distances x 1 and x 2 from the mean position the velocities of the pa20 Jul, 2021 (E)Time Period and Frequency
  10. 10An electron having de-Broglie wavelength is incident on a target in a X -ray tube. Cut-off wavelength of emitted X -ray is:20 Jul, 2021 (E)Matter Waves
  11. 11A body rolls down an inclined plane without slipping. The kinetic energy of rotation is 50 % of its translational kinetic energy. The body i20 Jul, 2021 (E)Rotational kinematics
  12. 12If time t , velocity v , and angular momentum l are taken as the fundamental units. Then the dimension of mass ( m ) in terms of t , v and l20 Jul, 2021 (E)Dimensions
  13. 13The correct relation between the degrees of freedom f and the ratio of specific heat is:20 Jul, 2021 (E)Degree of Freedom and Specific Heat
  14. 14For a certain radioactive process, the graph between ln R and t ( sec ) is obtained as shown in the figure. Then the value of half life for 20 Jul, 2021 (E)Radioactivity
  15. 15Consider a binary star system of star A and star B with masses m A and m B revolving in a circular orbit of radii r A and r B , respectively20 Jul, 2021 (E)Newton's Law of Gravitation
  16. 16At an angle of 30 to the magnetic meridian, the apparent dip is 45 . Find the true dip:20 Jul, 2021 (E)Earths magnetic field
  17. 17A body at rest is moved along a horizontal straight line by a machine delivering a constant power. The distance moved by the body in time t 20 Jul, 2021 (E)Rest and Motion
  18. 18Two vectors P and Q have equal magnitudes. If the magnitude of P + Q is n times the magnitude of P - Q , then angle between P and Q is20 Jul, 2021 (E)Addition and Subtraction of Vectors
  19. 19Two small drops of mercury each of radius R coalesce to form a single large drop. The ratio of total surface energy before and after the cha20 Jul, 2021 (E)Surface tension
  20. 20The magnetic susceptibility of a material of a rod is 499 . Permeability in vacuum is 4 10 - 7 Hm - 1 . Absolute permeability of the materia20 Jul, 2021 (E)Magnetism and Properties of Magnet
  21. 21A zener diode having zener voltage 8 V and power dissipation rating of 0 . 5 W is connected across a potential divider arranged with maximum20 Jul, 2021 (E)Diodes
  22. 22A body of mass m is launched up on a rough inclined plane making an angle of 30 with the horizontal. The coefficient of friction between the20 Jul, 2021 (E)Frictional force
  23. 23In the given figure switches S 1 and S 2 are in open condition. The resistance across a b when the switches S 1 and S 2 are closed is ______20 Jul, 2021 (E)Resistance and Resistivity
  24. 24Two bodies, a ring and a solid cylinder of same material are rolling down without slipping an inclined plane. The radii of the bodies are sa20 Jul, 2021 (E)Rolling without Slipping
  25. 25For the forward biased diode characteristics shown in the figure, the dynamic resistance at I D = 3 mA will be ________ .20 Jul, 2021 (E)Diodes
  26. 26A series LCR circuit of R = 5 , L = 20 mH and C = 0 . 5 F is connected across an AC supply of 250 V , having variable frequency. The power d20 Jul, 2021 (E)AC Circuits
  27. 27One mole of an ideal gas at 27 C is taken from A to B as shown in the given P V indicator diagram. The work done by the system will be _____20 Jul, 2021 (E)First Law of Thermodynamics
  28. 28A certain metallic surface is illuminated by monochromatic radiation of wavelength . The stopping potential for photoelectric current for th20 Jul, 2021 (E)Photoelectric Effect
  29. 29A body rotating with an angular speed of 600 rpm is uniformly accelerated to 1800 rpm in 10 sec . The number of rotations made in the proces20 Jul, 2021 (E)Rotational kinematics
  30. 30A radioactive substance decays to 1 16 th of its initial activity in 80 days. The half life of the radioactive substance expressed in days i20 Jul, 2021 (E)Radioactivity

Frequently Asked Questions

1.How many questions are in the JEE Main 2021 20th July Evening Shift paper?

This paper has 90 questions in total - 30 each from Chemistry, Mathematics, and Physics.

2.Can I practise questions from just one subject?

Yes. Use the Chemistry, Mathematics, and Physics tabs at the top of the page to jump directly to that subject's question set within this shift.

3.Is this the same paper for all students who appeared in the evening shift?

JEE Main uses different question sets across shifts and sessions to maintain exam integrity, so this page reflects the specific paper administered in the 20th July 2021 evening shift.

4.Where can I find the morning shift paper for the same date?

The JEE Main 2021 20th July Morning Shift paper is listed separately - you can switch to it from the "JEE Main Paper Wise PYQs" panel, under JEE Main 20th July 2021.

5.What is the structure of the JEE Main 2021 20th July Evening Shift paper?

The JEE Main 2021 20th July Evening Shift paper on MARKS has 90 questions, organised by subject:

  • Chemistry: 30 questions - 20 single-correct and 10 numerical-value.
  • Mathematics: 30 questions - 20 single-correct and 10 numerical-value.
  • Physics: 30 questions - 20 single-correct and 10 numerical-value.
6.What is the difficulty level of the JEE Main 2021 20th July Evening Shift paper?

Each question on MARKS carries a difficulty rating. Of the 90 rated questions in this paper, 38 (42%) are easy, 34 (38%) are medium and 18 (20%) are hard. Subject wise:

  • Chemistry: 12 easy, 10 medium, 8 hard
  • Mathematics: 11 easy, 12 medium, 7 hard
  • Physics: 15 easy, 12 medium, 3 hard
7.Which chapters had the most questions in the JEE Main 2021 20th July Evening Shift paper?

The chapters with the most questions in each subject were:

  • Chemistry: General Organic Chemistry (3), Structure of Atom (3), and Amines (2).
  • Mathematics: Definite Integration (3), Sequences and Series (3), and Differential Equations (2).
  • Physics: Rotational Motion (3), Alternating Current (2), and Dual Nature of Matter (2).
8.Are there any out-of-syllabus questions in the JEE Main 2021 20th July Evening Shift paper?

Yes. 20 of the 90 questions in this paper are marked on MARKS as outside the current syllabus. You can still practise them for the concept, but they are a lower priority if you are short on time.

9.Where can I find the solutions for the JEE Main 2021 20th July Evening Shift paper?

Open any question on this page. Its page shows the correct answer and, where one is available, the worked solution. A downloadable PDF of the whole shift is coming soon.

10.How should I use the JEE Main 2021 20th July Evening Shift paper to check my preparation?

Set a timer, attempt the 90 questions as you would in the exam, and only then open the answers. Note which subjects and chapters cost you the most marks, and revise those first using the chapter-wise practice for JEE Main. Repeating this with other papers shows whether the same weak spots keep coming back.

11.Will the JEE Main 2021 20th July Evening Shift paper help me prepare for JEE Main 2027?

Yes. Every past paper shows the question styles and topics JEE Main has asked before, and a solved paper gives you a realistic benchmark for speed and accuracy. Use it along with the other papers to spot the chapters that keep returning.