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The d-electron configuration of [Ru(en)₃]Cl₂ and [Fe(H₂O)₆]Cl₂, respectively are:

1) t42g e2g and t62g eog 2) t62g eog and t62g eog 3) t42g e2g and t42g e2g 4) t62g e0g and t42g e2g Answer: (4)... View Article

Consider the hypothetical situation where the azimuthal quantum number, l, takes values 0, 1, 2, …… n + 1, where n is the principal quantum number. Then, the element with atomic number:

1) 13 has a half-filled valence subshell 2) 9 is the first alkali metal 3) 8 is the first noble gas 4) 6 has a 2p-valence subshell Answer:... View Article

100 mL of 0.1 M HCl is taken in a beaker and to it, 100 mL of 0.1 M NaOH is added in steps of 2 mL and the pH is continuously measured. Which of the following graphs correctly depicts the change in pH?

Answer: (3) initially pH will be acidic < 7 at eq pH pH = 7 & finally pH will be basic > 7... View Article

The incorrect statement(s) among (a) – (d) regarding acid rain is (are):

(a) It can corrode water pipes. (b) It can damage structures made up of stone. (c) It cannot cause respiratory ailments in animals (d) It is... View Article

The increasing order of the reactivity of the following compounds in nucleophilic addition reaction is: Propanal, Benzaldehyde, Propanone, Butanone

1) Benzaldehyde < Propanal < Propanone < Butanone 2) Propanal < Propanone < Butanone < Benzaldehyde 3) Butanone <... View Article

The decreasing order of reactivity of the following compounds towards nucleophilic substitution (S_N2) is:

1) (III) > (II) > (IV) > (I) 2) (IV) > (II) > (III) > (I) 3) (II) > (III) > (IV) > (I) 4) (II) > (III) >... View Article

Complex A has a composition of H₁₂O₆Cl₃Cr. If the complex on treatment with conc. H2SO4 loses 13.5% of its original mass, the correct molecular formula of A is: [Given: the atomic mass of Cr = 52 amu and Cl = 35 amu]

1) [Cr(H2O)5Cl]Cl2 .H2O 2) [Cr(H2O)4Cl2]Cl.2H2O 3) [Cr(H2O)3Cl3].3H2O 4) [Cr(H2O)6]Cl3 Answer: (2) Let x molecule of water are lost then... View Article

Among the statements (I–IV), the correct ones are:

(I) Be has a smaller atomic radius compared to Mg. (II) Be has higher ionization enthalpy than Al. (III) Charge/radius ratio of Be is greater... View Article

An ionic micelle is formed on the addition of

1) liquid diethyl ether to aqueous NaCl solution 2) sodium stearate to pure toluene 3) excess water to liquid 4) excess water to liquid... View Article

Match the following drugs with their therapeutic actions:

(i) Ranitidine (a) Antidepressant (ii) Nardil (Phenelzine) (b) Antibiotic (iii)Chloramphenicol (c) Antihistamine (iv) Dimetane... View Article

The five successive ionization enthalpies of an element are 800, 2427, 3658, 25024 and 32824 kJ mol^–1. The number of valence electrons in the element is:

1) 2 2) 4 3) 3 4) 5 Answer: (3) Fourth & Fifth I.E. are very high (periodic properties) indicating the presence of three valence shell... View Article

In connection with the circuit drawn below, the value of current flowing through the 2kΩ resistor is _______ × 10^–4 A.

Answer: 25 In zener diode there will be o change in current after 5V Zener diode breakdown ⇒ i = 5 / 2 × 103 ⇒ i = 2.5... View Article

An unpolarized light beam is incident on the polarizer of a polarization experiment and the intensity of the light beam emerging from the analyzer is measured as 100 Lumens. Now, if the analyzer is rotated around the horizontal axis (direction of light) by 30° in clockwise direction, the intensity of emerging light will be________ Lumens.

Answer: 75 Given: I0 = 100 lumens, θ = 30o Inet = I0 cos2θ Inet = 100 × (√3/2)2 = 100 × 3 / 4 Inet = 75 lumens... View Article

A common transistor radio set requires 12 V (D.C.) for its operation. The D.C. source is constructed by using a transformer and a rectifier circuit, which are operated at 220 V (A.C.) on standard domestic A.C. supply. The number of turns of the secondary coil are 24, then the number of turns of the primary are ______.

Answer: 440 Given, Primary voltage, Vp = 220 V Secondary voltage, vs = 12 V No. of turns in secondary coil is Ns = 24 No. of turns in... View Article

A hydraulic press can lift 100 kg when a mass ‘m’ is placed on the smaller piston. It can lift _______ kg when the diameter of the larger piston is increased by 4 times and that of the smaller piston is decreased by 4 times keeping the same mass ‘m’ on the smaller piston.

Answer: 25600 Atmospheric pressure P0 will be acting on both the limbs of the hydraulic lift. Applying pascal’s law for the same liquid... View Article

An electromagnetic wave of frequency 5 GHz, is travelling in a medium whose relative electric permittivity and relative magnetic permeability both are 2. Its velocity in this medium is _______ × 10⁷ m/s.

Answer: 15 Given: f = 5 GHz εr =2 μr = 2 Velocity of wave ⇒ v = c / n ....(1) Where, n = √μrεr and c =... View Article

An inclined plane is bent in such a way that the vertical cross-section is given by y = x² / 4 where y is in vertical and x in horizontal direction. If the upper surface of this curved plane is rough with a coefficient of friction μ = 0.5, the maximum height in cm at which a stationary block will not slip downward is _____ cm.

Answer: 25 Given, y = x2 / 4 μ = 0.5 Condition for block will not slip downward mg sin θ = μmg cos θ ⇒ tan... View Article

The coefficient of static friction between a wooden block of mass 0.5 kg and a vertical rough wall is 0.2. The magnitude of horizontal force that should be applied on the block to keep it adhere to the wall will be ______ N. [g = 10 ms^-2]

Answer: 25 Given: μs = 0.2 m = 0.5 kg g = 10 m/s2 We know that fs = μsN and .... (1) To keep the block adhere to the wall Here, N... View Article

An audio signal υ_m = 20sin2π(1500t) amplitude modulates a carrier υ_c =80 sin 2π (100,000t). The value of percent modulation is ________.

Answer: 25 We know that, modulation index = Am / Ac From given equations, Am = 20 and Ac = 80 Percentage modulation index = Am / Ac ×... View Article

A ball with a speed of 9 m/s collides with another identical ball at rest. After the collision, the direction of each ball makes an angle of 30° with the original direction. The ratio of velocities of the balls after collision is x : y, where x is _________.

Answer: 1 Momentum is conserved just before and just after the collision in both x-y direction. In y-direction, pi = 0 pf = mv1 sin30o... View Article