JEE Main 2021 (Online) 25th July Evening Shift

Maleic anhydride can prepared by :

[where \(Et \Rightarrow - {C_2}{H_5}{}^tBu \Rightarrow {(C{H_3})_3}C -\)]Consider the above reaction sequence, Product "A" and Product "B" formed respectively are :

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

Which among the following is the strongest acid ?

Which one of the following is correct structure for cytosine?

In the following the correct bond order sequence is :

Identify the species having one \(\pi\)-bond and maximum number of canonical forms from the following :

Assuming that Ba(OH)2 is completely ionised in aqueous solution under the given conditions the concentration of H3O+ ions in 0.005 M aqueous solution of Ba(OH)2 at 298 K is ______________ \(\times\) 10\(-\)12 mol L\(-\)1. (Nearest integer)

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 average rate of the reaction is ____________ \(\times\) 10\(-\)1 mol L\(-\)1 h\(-\)1. (in nearest integer)

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

A reaction of benzonitrile with one equivalent CH3MgBr followed by hydrolysis produces a yellow liquid "P". The compound "P" will give positive _________.

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

Which one of the following metal complexes is most stable?

The spin only magnetic moments (in BM) for free Ti3+, V2+ and Sc3+ ions respectively are :(At.No. Sc : 21, Ti : 22, V : 23)

Which one of the following metals forms interstitial hydride easily?

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

Given below are two statements :Statement I : Chlorofluoro breakdown by radiation in the visible energy region and release chlorine gas in the atmosphere which then reacts with stratospheric ozone.Statement II : Atmospheric ozone reacts wit...

An LPG cylinder contains gas at a pressure of 300 kPa at 27\(^\circ\). The cylinder can withstand the pressure of 1.2 \(\times\) 106 Pa. The room in which the cylinder is kept catches fire. The minimum temperature at which the bursting of c...

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

Match List I with List II : (Both having metallurgical terms)
.tg {border-collapse:collapse;border-spacing:0;}
.tg td{border-color:black;border-style:solid;border-width:1px;font-family:Arial, sans-serif;font-size:14px;
overflow:hidden;pa...

The ionic radii of F\(-\) and O2\(-\) respectively are 1.33\(\mathop A\limits^o\) and 1.4\(\mathop A\limits^o\), while the covalent radius of N is 0.74\(\mathop A\limits^o\).The correct statement for the ionic radius of N3\(-\) from the ...

A biodegradable polyamide can be made from :

0.8 g of an organic compound was analyzed by Kjeldahl's method for the estimation of nitrogen. If the percentage of nitrogen in the compound was found to be 42%, then ______________ mL of 1 M H2SO4 would have been neutralized by the ammonia...

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

Match List I with List II :
.tg {border-collapse:collapse;border-spacing:0;}
.tg td{border-color:black;border-style:solid;border-width:1px;font-family:Arial, sans-serif;font-size:14px;
overflow:hidden;padding:10px 5px;word-break:normal;}...

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 the substance 'X' is ______________ g mol\(-\)1. (Nearest integer).[Given Kb for CCl4 is 5.0 K kg mol\(-\)1]

The number of significant figures in 0.00340 is ____________.

An accelerated electron has a speed of 5 \(\times\) 106 ms\(-\)1 with an uncertainty of 0.02%. The uncertainty in finding its location while in motion is x \(\times\) 10\(-\)9 m. The value of x is ____________. (Nearest integer)[Use mass of...

Match List I with List II :


List-IExample of colloids
List - IIClassification




(a) Cheese
(i) dispersion of liquid in liquid


(b) Pumice stone
(ii) dispersion of liquid in gas


(c) Hair cream...

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 is ____________ J. (Nearest integer)

If the lines \({{x - k} \over 1} = {{y - 2} \over 2} = {{z - 3} \over 3}\) and \({{x + 1} \over 3} = {{y + 2} \over 2} = {{z + 3} \over 1}\) are co-planar, then the value of k is _____________.

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

If the greatest value of the term independent of 'x' in the expansion of \({\left( {x\sin \alpha + a{{\cos \alpha } \over x}} \right)^{10}}\) is \({{10!} \over {{{(5!)}^2}}}\), then the value of 'a' is equal to :

The lowest integer which is greater than \({\left( {1 + {1 \over {{{10}^{100}}}}} \right)^{{{10}^{100}}}}\) is ______________.

Let n\(\in\)N and [x] denote the greatest integer less than or equal to x. If the sum of (n + 1) terms \({}^n{C_0},3.{}^n{C_1},5.{}^n{C_2},7.{}^n{C_3},.....\) is equal to 2100 . 101, then \(2\left[ {{{n - 1} \over 2}} \right]\) is equal to ...

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

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 the given circle and the vertex of the parabola, x2 \(-\) 6x \(-\) y + 13 = 0, has y-intercept equal to ______________.

If \(f(x) = \left\{ {\matrix{ {\int\limits_0^x {\left( {5 + \left| {1 - t} \right|} \right)dt,} } & {x > 2} \cr {5x + 1,} & {x \le 2} \cr } } \right.\), then

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

Let y = y(x) be the solution of the differential equation xdy = (y + x3 cosx)dx with y(\(\pi\)) = 0, then \(y\left( {{\pi \over 2}} \right)\) is equal to :

Let a curve y = f(x) pass through the point (2, (loge2)2) and have slope \({{2y} \over {x{{\log }_e}x}}\) for all positive real value of x. Then the value of f(e) is equal to ______________.

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 circle with BC as diameter passes through the point :

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

Consider the functionwhere P(x) is a polynomial such that P'' (x) is always a constant and P(3) = 9. If f(x) is continuous at x = 2, then P(5) is equal to _____________.

Consider the statement "The match will be played only if the weather is good and ground is not wet". Select the correct negation from the following :

The number of distinct real roots of \(\left| {\matrix{ {\sin x} & {\cos x} & {\cos x} \cr {\cos x} & {\sin x} & {\cos x} \cr {\cos x} & {\cos x} & {\sin x} \cr } } \right| = 0\) in the interval $$ - {\pi \over 4} \le x \l...

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

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

Let X be a random variable such that the probability function of a distribution is given by \(P(X = 0) = {1 \over 2},P(X = j) = {1 \over {{3^j}}}(j = 1,2,3,...,\infty )\). Then the mean of the distribution and P(X is positive and even) resp...

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 value of n is ______________.