Identify (A) in the following reaction sequence :

If enthalpy of atomisation for Br2(1) is x kJ/mol and bond enthalpy for Br2 is y kJ/mol, the relation between them :

If the magnetic moment of a dioxygen species is 1.73 B.M, it may be :

[Pd(F)(Cl)(Br)(I)]2– has n number of geometrical isomers. Then, the spin-only magnetic moment and crystal field stabilis

The Ksp for the following dissociation is 1.6 × 10–5 $$PbC{l_{2(s)}} \leftrightharpoons Pb_{(aq)}^{2 + } + 2Cl_{(aq)}^ -

The correct order of heat of combustion for following alkadienes is :

For the following reactions $$A\buildrel {700K} \over \longrightarrow {\mathop{\rm Product}\nolimits} $$ $$A\mathrel{\m

The increasing order of basicity for the following intermediates is (from weak to strong)

The electronic configurations of bivalent europium and trivalent cerium are (atomic number : Xe = 54, Ce = 58, Eu = 63)

How much amount of NaCl should be added to 600 g of water ($$\rho $$ = 1.00 g/mL) to decrease the freezing point of wate

The mass percentage of nitrogen in histamine is _____.

108 g of silver (molar mass 108 g mol–1) is deposited at cathode from AgNO3(aq) solution by a certain quantity of electr

The molarity of HNO3 in a sample which has density 1.4 g/mL and mass percentage of 63% is _____. (Molecular Weight of H

The hardness of a water sample containing 10–3 M MgSO4 expressed as CaCO3 equivalents (in ppm) is ______. (molar mass of

The de Broglie wavelength of an electron in the 4th Bohr orbit is :

The major product (Y) in the following reactions is :

Complex X of composition Cr(H2O)6Cln has a spin only magnetic moment of 3.83 BM. It reacts with AgNO3 and shows geometri

The compound that cannot act both as oxidising and reducing agent is :

Which of these will produce the highest yield in Friedel Crafts reaction?

The major product Z obtained in the following reaction scheme is :

The acidic, basic and amphoteric oxides, respectively, are :

B has a smaller first ionization enthalpy than Be. Consider the following statements : (I) It is easier to remove 2p ele

If ƒ'(x) = tan–1(secx + tanx), $$ - {\pi \over 2} < x < {\pi \over 2}$$, and ƒ(0) = 0, then ƒ(1) is equal to :

The value of $$\int\limits_0^{2\pi } {{{x{{\sin }^8}x} \over {{{\sin }^8}x + {{\cos }^8}x}}} dx$$ is equal to :

In a box, there are 20 cards, out of which 10 are lebelled as A and the remaining 10 are labelled as B. Cards are drawn

Let z be complex number such that $$\left| {{{z - i} \over {z + 2i}}} \right| = 1$$ and |z| = $${5 \over 2}$$. Then the

A spherical iron ball of 10 cm radius is coated with a layer of ice of uniform thickness the melts at a rate of 50 cm3/m

If the number of five digit numbers with distinct digits and 2 at the 10th place is 336 k, then k is equal to :

Let ƒ be any function continuous on [a, b] and twice differentiable on (a, b). If for all x $$ \in $$ (a, b), ƒ'(x) >

The projection of the line segment joining the points (1, –1, 3) and (2, –4, 11) on the line joining the points (–1, 2,

If for x $$ \ge $$ 0, y = y(x) is the solution of the differential equation (x + 1)dy = ((x + 1)2 + y – 3)dx, y(2) = 0,

The coefficient of x4 is the expansion of (1 + x + x2)10 is _____.

If for some $$\alpha $$ and $$\beta $$ in R, the intersection of the following three places x + 4y – 2z = 1 x + 7y – 5z

The number of distinct solutions of the equation $${\log _{{1 \over 2}}}\left| {\sin x} \right| = 2 - {\log _{{1 \over

The integral $$\int {{{dx} \over {{{(x + 4)}^{{8 \over 7}}}{{(x - 3)}^{{6 \over 7}}}}}} $$ is equal to : (where C is a c

If $$f(x) = \left\{ {\matrix{ {{{\sin (a + 2)x + \sin x} \over x};} & {x < 0} \cr {b\,\,\,\,\,\,\,\,\,\,\

Let C be the centroid of the triangle with vertices (3, –1), (1, 3) and (2, 4). Let P be the point of intersection of th

The value of $${\cos ^3}\left( {{\pi \over 8}} \right)$$$${\cos}\left( {{3\pi \over 8}} \right)$$+$${\sin ^3}\left( {{

If for all real triplets (a, b, c), ƒ(x) = a + bx + cx2; then $$\int\limits_0^1 {f(x)dx} $$ is equal to :

If e1 and e2 are the eccentricities of the ellipse, $${{{x^2}} \over {18}} + {{{y^2}} \over 4} = 1$$ and the hyperbola,

Let the observations xi (1 $$ \le $$ i $$ \le $$ 10) satisfy the equations, $$\sum\limits_{i = 1}^{10} {\left( {{x_1} -

The number of real roots of the equation, e4x + e3x – 4e2x + ex + 1 = 0 is :

In a fluorescent lamp choke (a small transformer) 100 V of reverse voltage is produced when the choke current changes un

Both the diodes used in the circuit shown are assumed to be ideal and have negligible resistance when these are forward

A body of mass m = 10 kg is attached to one end of a wire of length 0.3 m. The maximum angular speed (in rad s–1) with w

The distance x covered by a particle in one dimensional motion varies with time t as x2 = at2 + 2bt + c. If the accelera

One end of a straight uniform 1m long bar is pivoted on horizontal table. It is released from rest when it makes an angl

Water flows in a horizontal tube (see figure). The pressure of water changes by 700 Nm–2 between A and B where the area

Three solid spheres each of mass m and diameter d are stuck together such that the lines connecting the centres form an

An electric dipole of moment $$\overrightarrow p = \left( { - \widehat i - 3\widehat j + 2\widehat k} \right) \times {1

Three harmonic waves having equal frequency $$\nu $$ and same intensity $${I_0}$$, have phase angles 0, $${\pi \over 4}

A charged particle of mass 'm' and charge 'q' moving under the influence of uniform electric field $$E\overrightarrow i

Which of the following is an equivalent cyclic process corresponding to the thermodynamic cyclic given in the figure ? w

In the given circuit diagram, a wire is joining points B and D. The current in this wire is :

Two particles of equal mass m have respective initial velocities $$u\widehat i$$ and $$u\left( {{{\widehat i + \widehat

If the screw on a screw-gauge is given six rotations, it moves by 3 mm on the main scale. If there are 50 divisions on t

Consider two ideal diatomic gases A and B at some temperature T. Molecules of the gas A are rigid, and have a mass m. Mo

A particle moving with kinetic energy E has de Broglie wavelength $$\lambda $$. If energy $$\Delta $$E is added to its e

Consider a force $$\overrightarrow F = - x\widehat i + y\widehat j$$ . The work done by this force in moving a particl

A body A of mass m is moving in a circular orbit of radius R about a planet. Another body B of mass $${m \over 2}$$ coll

Consider a sphere of radius R which carries a uniform charge density $$\rho $$. If a sphere of radius $${{R \over 2}}$$

The electric fields of two plane electromagnetic plane waves in vacuum are given by $$\overrightarrow {{E_1}} = {E_0}\w

A long, straight wire of radius a carries a current distributed uniformly over its cross-section. The ratio of the magne

Radiation, with wavelength 6561 $$\mathop A\limits^o $$ falls on a metal surface to produce photoelectrons. The electron

The aperture diameter of a telescope is 5m. The separation between the moon and the earth is 4 × 105 km. With light of w

A vessel of depth 2h is half filled with a liquid of refractive index $$2\sqrt 2 $$ and the upper half with another liqu

A quantity f is given by $$f = \sqrt {{{h{c^5}} \over G}} $$ where c is speed of light, G universal gravitational consta