JEE Main 2021 (Online) 25th July Evening Shift

Paper was held on
Sun, Jul 25, 2021 9:30 AM

## Chemistry

In the following the correct bond order sequence is :

View Question A biodegradable polyamide can be made from :

View Question Match List I with List II :
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View Question Which one of the following metal complexes is most stable?

View Question Match List I with List II : (Both having metallurgical terms)
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View Question The ionic radii of F$$-$$ and O2$$-$$ respectively are 1.33$$\mathop A\limits^o $$ and 1.4$$\mathop A\limits^o $$, while

View Question The correct decreasing order of densities of the following compounds is :

View Question Consider the above reaction, the product "P" is :

View Question A reaction of benzonitrile with one equivalent CH3MgBr followed by hydrolysis produces a yellow liquid "P". The compound

View Question The spin only magnetic moments (in BM) for free Ti3+, V2+ and Sc3+ ions respectively are :(At.No. Sc : 21, Ti : 22, V :

View Question Which one of the following is correct structure for cytosine?

View Question Identify the species having one $$\pi$$-bond and maximum number of canonical forms from the following :

View Question Which one of the following metals forms interstitial hydride easily?

View Question Maleic anhydride can prepared by :

View Question Given below are two statements :Statement I : Chlorofluoro breakdown by radiation in the visible energy region and relea

View Question [where $$Et \Rightarrow - {C_2}{H_5}{}^tBu \Rightarrow {(C{H_3})_3}C - $$]Consider the above reaction sequence, Product

View Question Match List I with List II :
List-IExample of colloids
List - IIClassification
(a) Cheese
(i)

View Question What is the major product "P" of the following reaction?

View Question Identify the process in which change in the oxidation state is five :

View Question Which among the following is the strongest acid ?

View Question A system does 200 J of work and at the same time absorbs 150 J of heat. The magnitude of the change in internal energy i

View Question An accelerated electron has a speed of 5 $$\times$$ 106 ms$$-$$1 with an uncertainty of 0.02%. The uncertainty in findin

View Question Number of electrons present in 4f orbital of Ho3+ ion is ____________. (Given Atomic No. of Ho = 67)

View Question Consider the above chemical reaction. The total number of stereoisomers possible for Product 'P' is _____________.

View Question For a chemical reaction A $$\to$$ B, it was found that concentration of B is increased by 0.2 mol L$$-$$ in 30 min. The

View Question The number of significant figures in 0.00340 is ____________.

View Question Assuming that Ba(OH)2 is completely ionised in aqueous solution under the given conditions the concentration of H3O+ ion

View Question 0.8 g of an organic compound was analyzed by Kjeldahl's method for the estimation of nitrogen. If the percentage of nitr

View Question When 3.00 g of a substance 'X' is dissolved in 100 g of CCl4, it raises the boiling point by 0.60 K. The molar mass of t

View Question An LPG cylinder contains gas at a pressure of 300 kPa at 27$$^\circ$$. The cylinder can withstand the pressure of 1.2 $$

View Question ## Mathematics

The sum of all those terms which are rational numbers in the expansion of (21/3 + 31/4)12 is :

View Question The first of the two samples in a group has 100 items with mean 15 and standard deviation 3. If the whole group has 250

View Question If $$f(x) = \left\{ {\matrix{
{\int\limits_0^x {\left( {5 + \left| {1 - t} \right|} \right)dt,} } & {x > 2} \

View Question If the greatest value of the term independent of 'x' in the expansion of $${\left( {x\sin \alpha + a{{\cos \alpha } \ov

View Question Consider the statement "The match will be played only if the weather is good and ground is not wet". Select the correct

View Question The value of $$\cot {\pi \over {24}}$$ is :

View Question The lowest integer which is greater than $${\left( {1 + {1 \over {{{10}^{100}}}}} \right)^{{{10}^{100}}}}$$ is _________

View Question The value of the integral $$\int\limits_{ - 1}^1 {\log \left( {x + \sqrt {{x^2} + 1} } \right)dx} $$ is :

View Question Let a, b and c be distinct positive numbers. If the vectors $$a\widehat i + a\widehat j + c\widehat k,\widehat i+\wideha

View Question If [x] be the greatest integer less than or equal to x, then $$\sum\limits_{n = 8}^{100} {\left[ {{{{{( - 1)}^n}n} \over

View Question The number of distinct real roots of $$\left| {\matrix{
{\sin x} & {\cos x} & {\cos x} \cr
{\cos x} &

View Question If $$\left| {\overrightarrow a } \right| = 2,\left| {\overrightarrow b } \right| = 5$$ and $$\left| {\overrightarrow a

View Question The number of real solutions of the equation, x2 $$-$$ |x| $$-$$ 12 = 0 is :

View Question Consider function f : A $$\to$$ B and g : B $$\to$$ C (A, B, C $$ \subseteq $$ R) such that (gof)$$-$$1 exists, then :

View Question If $$P = \left[ {\matrix{
1 & 0 \cr
{{1 \over 2}} & 1 \cr
} } \right]$$, then P50 is :

View Question Let X be a random variable such that the probability function of a distribution is given by $$P(X = 0) = {1 \over 2},P(X

View Question If a tangent to the ellipse x2 + 4y2 = 4 meets the tangents at the extremities of it major axis at B and C, then the cir

View Question Let the equation of the pair of lines, y = px and y = qx, can be written as (y $$-$$ px) (y $$-$$ qx) = 0. Then the equa

View Question If $${}^n{P_r} = {}^n{P_{r + 1}}$$ and $${}^n{C_r} = {}^n{C_{r - 1}}$$, then the value of r is equal to :

View Question Let y = y(x) be the solution of the differential equation xdy = (y + x3 cosx)dx with y($$\pi$$) = 0, then $$y\left( {{\p

View Question Let n$$\in$$N and [x] denote the greatest integer less than or equal to x. If the sum of (n + 1) terms $${}^n{C_0},3.{}^

View Question Consider the functionwhere P(x) is a polynomial such that P'' (x) is always a constant and P(3) = 9. If f(x) is continuo

View Question The equation of a circle is Re(z2) + 2(Im(z))2 + 2Re(z) = 0, where z = x + iy. A line which passes through the center of

View Question If a rectangle is inscribed in an equilateral triangle of side length $$2\sqrt 2 $$ as shown in the figure, then the squ

View Question If $$\left( {\overrightarrow a + 3\overrightarrow b } \right)$$ is perpendicular to $$\left( {7\overrightarrow a - 5\o

View Question Let a curve y = f(x) pass through the point (2, (loge2)2) and have slope $${{2y} \over {x{{\log }_e}x}}$$ for all positi

View Question If a + b + c = 1, ab + bc + ca = 2 and abc = 3, then the value of a4 + b4 + c4 is equal to ______________.

View Question A fair coin is tossed n-times such that the probability of getting at least one head is at least 0.9. Then the minimum v

View Question If the co-efficient of x7 and x8 in the expansion of $${\left( {2 + {x \over 3}} \right)^n}$$ are equal, then the value

View Question If the lines $${{x - k} \over 1} = {{y - 2} \over 2} = {{z - 3} \over 3}$$ and $${{x + 1} \over 3} = {{y + 2} \over 2} =

View Question ## Physics

The relation between time t and distance x for a moving body is given as t = mx2 + nx, where m and n are constants. The

View Question In a simple harmonic oscillation, what fraction of total mechanical energy is in the form of kinetic energy, when the pa

View Question A force $$\overrightarrow F = (40\widehat i + 10\widehat j)N$$ acts on a body of mass 5 kg. If the body starts from res

View Question A prism of refractive index $$\mu$$ and angle of prism A is placed in the position of minimum angle of deviation. If min

View Question A heat engine has an efficiency of $${1 \over 6}$$. When the temperature of sink is reduced by 62$$^\circ$$C, its effici

View Question In the given potentiometer circuit arrangement, the balancing length AC is measured to be 250 cm. When the galvanometer

View Question Two ions having same mass have charges in the ratio 1 : 2. They are projected normally in a uniform magnetic field with

View Question A 10 $$\Omega$$ resistance is connected across 220V $$-$$ 50 Hz AC supply. The time taken by the current to change from

View Question A balloon was moving upwards with a uniform velocity of 10 m/s. An object of finite mass is dropped from the balloon whe

View Question If qf is the free charge on the capacitor plates and qb is the bound charge on the dielectric slab of dielectric constan

View Question Consider a planet in some solar system which has a mass double the mass of earth and density equal to the average densit

View Question Two ideal electric dipoles A and B, having their dipole moment p1 and p2 respectively are placed on a plane with their c

View Question Two spherical soap bubbles of radii r1 and r2 in vacuum combine under isothermal conditions. The resulting bubble has a

View Question The force is given in terms of time t and displacement x by the equation F = A cos Bx + C sin DtThe dimensional formula

View Question The given potentiometer has its wire of resistance 10$$\Omega$$. When the sliding contact is in the middle of the potent

View Question An electron moving with speed v and a photon moving with speed c, have same D-Broglie wavelength. The ratio of kinetic e

View Question The instantaneous velocity of a particle moving in a straight line is given as $$V = \alpha t + \beta {t^2}$$, where $$\

View Question A ray of light entering from air into a denser medium of refractive index $${4 \over 3}$$, as shown in figure. The light

View Question When radiation of wavelength $$\lambda$$ is incident on a metallic surface, the stopping potential of ejected photoelect

View Question Two vectors $$\overrightarrow X $$ and $$\overrightarrow Y $$ have equal magnitude. The magnitude of ($$\overrightarrow

View Question A system consists of two types of gas molecules A and B having same number density 2 $$\times$$ 1025/m3. The diameter of

View Question A light beam of wavelength 500 nm is incident on a metal having work function of 1.25 eV, placed in a magnetic field of

View Question A message signal of frequency 20 kHz and peak voltage of 20 volt is used to modulate a carrier wave of frequency 1 MHz

View Question A 16 $$\Omega$$ wire is bend to form a square loop. A 9V supply having internal resistance of 1$$\Omega$$ is connected a

View Question Two circuits are shown in the figure (a) & (b). At a frequency of ____________ rad/s the average power dissipated in

View Question From the given data, the amount of energy required to break the nucleus of aluminium $$_{13}^{27}$$Al is __________ x $$

View Question A force of F = (5y + 20)$$\widehat j$$ N acts on a particle. The work done by this force when the particle is moved from

View Question A solid disc of radius 20 cm and mass 10 kg is rotating with an angular velocity of 600 rpm, about an axis normal to its

View Question In a semiconductor, the number density of intrinsic charge carries at 27$$^\circ$$C is 1.5 $$\times$$ 1016/m3. If the se

View Question The nuclear activity of a radioactive element becomes $${\left( {{1 \over 8}} \right)^{th}}$$ of its initial value in 30

View Question