JEE Main 2021 (Online) 26th August Evening Shift

Which one of the following phenols does not give colour when condensed with phthalic anhydride in presence of conc. H2SO4 ?

Which one of the following compounds is not aromatic?

The number of stereoisomers possible for 1, 2-dimethyl cyclopropane is :

Given below are two statements : one is labelled as Assertion (A) and other is labelled as Reason (R). Assertion (A) : Sucrose is a disaccharide and a non-reducing sugar.Reason (R) : Sucrose involves glycosidic linkage between C1 of $$\beta...

The bond order and magnetic behaviour of \(O_2^ -\) ion are respectively :

The equilibrium constant Kc at 298 K for the reaction A + B \(\rightleftharpoons\) C + D is 100. Starting with an equimolar solution with concentrations of A, B, C and D all equal to 1M, the equilibrium concentration of D is ___________ $$\...

The reaction rate for the reaction[PtCl4]2\(-\) + H2O \(\rightleftharpoons\) [Pt(H2O)Cl3]\(-\) + Cl\(-\)was measured as a function of concentrations of different species. It was observed that $${{ - d\left[ {{{\left[ {PtC{l_4}} \right]}^{2 ...

The class of drug to which chlordiazepoxide with above structure belongs is :

Match List - I with List - II :Choose the most appropriate match :

The major product in the above reaction is :

Consider the given reaction, identify 'X' and 'Y' :

Indicate the complex/complex ion which did not show any geometrical isomerism :

Arrange the following Cobalt complexes in the order of increasing Crystal Field Stabilization Energy (CFSE) value.Complexes : $$\mathop {{{[Co{F_6}]}^{3 - }}}\limits_A ,\mathop {{{[Co{{({H_2}O)}_6}]}^{2 + }}}\limits_B ,\mathop {{{[Co{{(N{H_...

The overall stability constant of the complex ion [Cu(NH3)4]2+ is 2.1 \(\times\) 1013. The overall dissociations constant is y \(\times\) 10\(-\)14. Then y is __________. (Nearest integer)

For the galvanic cell,Zn(s) + Cu2+ (0.02 M) \(\to\) Zn2+ (0.04 M) + Cu(s),Ecell = ______________ \(\times\) 10\(-\)2 V. (Nearest integer)[Use : \(E_{Cu/C{u^{2 + }}}^0\) = \(-\) 0.34 V, \(E_{Zn/Z{n^{2 + }}}^0\) = + 0.76 V, $${{2.303RT} \over...

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : Photochemical smog causes cracking of rubber.Reason (R) : Presence of ozone, nitric oxide, acrolein, formaldehyde and...

The interaction energy of London forces between two particles is proportional to rx, where r is the distance between the particles. The value of x is :

Consider the given reaction, the product A is :

A chloro compound "A".(i) forms aldehydes on ozonolysis followed by the hydrolysis.(ii) when vaporized completely 1.53 g of A, gives 448 mL of vapour at STP.The number of carbon atoms in a molecule of compound A is ___________.

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).Assertion (A) : Heavy water is used for the study of reaction mechanism.Reason (R) : The rate of reaction for the cleavage of O - H bo...

Given below are two statements :Statement I : Sphalerite is a sulphide or of zinc and copper glance is a sulphide ore of copper.Statement II : It is possible to separate two sulphide ores by adjusting proportion of oil to water or by using ...

The number of non-ionisable hydrogen atoms present in the final product obtained from the hydrolysis of PCl5 is :

Chalcogen group elements are :

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).Assertion (A) : Barium carbonate is insoluble in water and is highly stable.Reason (R) : The thermal stability of the carbonates incre...

In the sulphur estimation, 0.471 g of an organic compound gave 1.44 g of barium sulphate. The percentage of sulphur in the compound is ____________%. (Nearest integer)(Atomic Mass of Ba = 137 u)

83 g of ethylene glycol dissolved in 625 g of water. The freezing point of the solution is ____________ K. (Nearest integer)[Use : Molal Freezing point depression constant of water = 1.86 K kg mol\(-\)1]Freezing Point of water = 273 KAtomic...

100 mL of Na3PO4 solution contains 3.45 g of sodium. The molarity of the solution is _____________ \(\times\) 10\(-\)2 mol L\(-\)1. (Nearest integer)[Atomic Masses - Na : 23.0 u, O : 16.0 u, P : 31.0 u]

A metal surface is exposed to 500 nm radiation. The threshold frequency of the metal for photoelectric current is 4.3 \(\times\) 1014 Hz. The velocity of ejected electron is ____________ \(\times\) 105 ms\(-\)1 (Nearest integer)[Use : h = 6...

The sol given below with negatively charged colloidal particles is :

For water \(\Delta\)vap H = 41 kJ mol\(-\)1 at 373 K and 1 bar pressure. Assuming that water vapour is an ideal gas that occupies a much larger volume than liquid water, the internal energy change during evaporation of water is ___________ ...

Let P be the plane passing through the point (1, 2, 3) and the line of intersection of the planes \(\overrightarrow r \,.\,\left( {\widehat i + \widehat j + 4\widehat k} \right) = 16\) and $$\overrightarrow r \,.\,\left( { - \widehat i + \w...

Let Q be the foot of the perpendicular from the point P(7, \(-\)2, 13) on the plane containing the lines \({{x + 1} \over 6} = {{y - 1} \over 7} = {{z - 3} \over 8}\) and \({{x - 1} \over 3} = {{y - 2} \over 5} = {{z - 3} \over 7}\). Then (...

The local maximum value of the function \(f(x) = {\left( {{2 \over x}} \right)^{{x^2}}}\), x > 0, is

Let a and b respectively be the points of local maximum and local minimum of the function f(x) = 2x3 \(-\) 3x2 \(-\) 12x. If A is the total area of the region bounded by y = f(x), the x-axis and the lines x = a and x = b, then 4A is equal t...

Let \(\left( {\matrix{ n \cr k \cr } } \right)\) denotes \({}^n{C_k}\) and $$\left[ {\matrix{
n \cr
k \cr

} } \right] = \left\{ {\matrix{
{\left( {\matrix{
n \cr
k \cr

} } \right),} & {if\,0 \le k \le ...

A circle C touches the line x = 2y at the point (2, 1) and intersects the circle C1 : x2 + y2 + 2y \(-\) 5 = 0 at two points P and Q such that PQ is a diameter of C1. Then the diameter of C is :

If \({\left( {\sqrt 3 + i} \right)^{100}} = {2^{99}}(p + iq)\), then p and q are roots of the equation :

The least positive integer n such that \({{{{(2i)}^n}} \over {{{(1 - i)}^{n - 2}}}},i = \sqrt { - 1}\) is a positive integer, is ___________.

If the value of the integral \(\int\limits_0^5 {{{x + [x]} \over {{e^{x - [x]}}}}dx = \alpha {e^{ - 1}} + \beta }\), where \(\alpha\), \(\beta\) \(\in\) R, 5\(\alpha\) + 6\(\beta\) = 0, and [x] denotes the greatest integer less than or equ...

The value of \(\int\limits_{ - {\pi \over 2}}^{{\pi \over 2}} {\left( {{{1 + {{\sin }^2}x} \over {1 + {\pi ^{\sin x}}}}} \right)} \,dx\) is

Let y(x) be the solution of the differential equation 2x2 dy + (ey \(-\) 2x)dx = 0, x > 0. If y(e) = 1, then y(1) is equal to :

A 10 inches long pencil AB with mid point C and a small eraser P are placed on the horizontal top of a table such that PC = \(\sqrt 5\) inches and \(\angle\)PCB = tan-1(2). The acute angle through which the pencil must be rotated about C s...

The point \(P\left( { - 2\sqrt 6 ,\sqrt 3 } \right)\) lies on the hyperbola \({{{x^2}} \over {{a^2}}} - {{{y^2}} \over {{b^2}}} = 1\) having eccentricity \({{\sqrt 5 } \over 2}\). If the tangent and normal at P to the hyperbola intersect it...

The locus of the mid points of the chords of the hyperbola x2 \(-\) y2 = 4, which touch the parabola y2 = 8x, is :

The domain of the function \({{\mathop{\rm cosec}\nolimits} ^{ - 1}}\left( {{{1 + x} \over x}} \right)\) is :

If \(\sum\limits_{r = 1}^{50} {{{\tan }^{ - 1}}{1 \over {2{r^2}}} = p}\), then the value of tan p is :

Let [t] denote the greatest integer less than or equal to t. Let f(x) = x \(-\) [x], g(x) = 1 \(-\) x + [x], and h(x) = min{f(x), g(x)}, x \(\in\) [\(-\)2, 2]. Then h is :

\(\mathop {\lim }\limits_{x \to 2} \left( {\sum\limits_{n = 1}^9 {{x \over {n(n + 1){x^2} + 2(2n + 1)x + 4}}} } \right)\) is equal to :

Consider the two statements :(S1) : (p \(\to\) q) \(\vee\) (\(\sim\) q \(\to\) p) is a tautology .(S2) : (p \(\wedge\) \(\sim\) q) \(\wedge\) (\(\sim\) p \(\wedge\) q) is a fallacy.Then :

Let \(A = \left( {\matrix{ 1 & 0 & 0 \cr 0 & 1 & 1 \cr 1 & 0 & 0 \cr } } \right)\). Then A2025 \(-\) A2020 is equal to :