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Four metallic plates each with a surface area of one side A, are placed at a distance d from each other. The two outer plates are connected to one point A and the two other inner plates to another point B . Then the capacitance of the system is

Applying Gauss’s law to this closed surface, we get, ∮E.ΔA=Qen/ε0=σΔA/ε0 ⇒ EΔA =σΔA/ε0 ⇒ E = σ/ε0 = Q/Aε0 Now, the potential difference... View Article

The most stable free radical among the following is (1)C6H5CH2C˙H2(2)C6H5C˙HCH3(3)CH3C˙HCH3(4)C˙6H5

Answer: (2)C6H5C˙HCH3 We know that a radical's stability is determined by its intrinsic energy. If the radical's internal energy is very... View Article

Consider the ground state of Cr atom (Z = 24). The numbers of electrons with the azimuthal quantum numbers, l = 1 and 2 are, respectively:

There are four quantum numbers that we are all familiar with: The size of the electron cloud and the energy level of the electron are... View Article

Which of the following will not give an iodoform test? A. Ethanal B. Ethanol C. 2 – propanone D. 3 – pentanone

Answer:(D) 3 - pentanone The iodoform test is used to evaluate whether a carbonyl compound with the formula CH3C=O and a secondary alcohol... View Article

Which will make the basic buffer? A) 50 mL of 0⋅1 M NaOH + 25 mL of 0⋅1M CH3COOH B) 100 mL of 0⋅1 M CH3COOH + 100 mL of 0⋅1M NaOH C) 100 mL of 0⋅1 M HCl + 200 mL of 0⋅1M NH4OH D) 100 mL of 0⋅1 M HCl + 100 mL of 0⋅1M NaOH

Answer: (c) 100 mL of 0⋅1 M HCl + 200 mL of 0⋅1M NH4OH We'll start by learning about the fundamental buffer solution notion. The basic... View Article

The most reactive element in the halogen group is …………. A. Astatine B. Iodine C. Chlorine D. Fluorine

Answer: Fluorine On the periodic table, the halogens are to the left of the noble gases. Fluorine (F), chlorine (Cl), bromine (Br), iodine... View Article

A compound is formed by cation C and anion A. The anions form hexagonal close packed (HCP) lattice and the actions occupy 75% of octahedral voids. What is the formula of the compound?

Answer: C3A4 In hexagonal close packed (HCP) lattice, the number of atoms = 6 The number of atoms is always equal to the number of... View Article

The rate of a first order reaction is 0.04 molL⁻¹s⁻¹ at 10 seconds and 0.03 molL⁻¹s⁻¹ at 20 seconds after initiation of the reaction. What is the half-life period of the reaction?

We know that for a first-order reaction - K = 2.303/t2−t1.log[A]1/[A]2 Here, t2 = final time; [A]2 = final concentration t1 = initial time;... View Article

What is the maximum spin multiplicity for 4d-orbital? (a).4 (b).6 (c).5 (d).0

Answer: (b) 6 For the same spatial electronic wave-function, spin multiplicity is the number of possible orientations of the spin angular... View Article

How many grams of concentrated nitric acid solution should be used to prepare 250mL of 2 M HNO3? The concentrated acid is 70 % (w/w) HNO3 .

Given that, 2M HNO3 means 2 moles of HNO3 in 1000mL of solution. Therefore, in 250mL solution we have 2/1000 × 250 = 0.5moles Molecular weight... View Article

Which of the following is the strongest base?

a) b) c) Answer: (c) Benzyl amine In acid-base reactions, strong bases are those that can remove a proton from a very weak acid, such... View Article

Acidic hydrogen is present in: A. Ethyne B. Ethene C. Benzene D. Ethane

Answer: a) Ethyne It appears that acidic hydrogen is released as the H+ ion. As a result, any H-atom bonded to another atom or group of atoms... View Article

What is the packing efficiency of bcc?

Body centred cubic unit cell- Here, the atoms are present at the corners of the cube and also one in the centre of the cube. Thus, there are two... View Article

Geometric representation of age structure is a characteristic of :

Geometric representation of age structure is a characteristic of population Population A discrete assemblage of entities with... View Article

Which of the following molecules have zero dipole moment? (a) NH3 (b)H2O (c)BeF2 (d)SO2

The correct answer is (c)BeF2 In a beryllium fluoride molecule, the bond angle between the two beryllium-fluorine bonds is 180o.... View Article

Statement – I: An electric dipole is placed at the centre of a hollow sphere. The flux of the electric field through the sphere is zero but the electric field is not zero anywhere in the sphere. Statement – II: If R is the radius of a solid metallic sphere and Q be the total charge on it. The electric field at any point on the spherical surface of radius r (< R) is zero but the electric flux passing through this closed spherical surface of radius r is not zero. In the light of the above statements Choose the correct answer from the option given below: a. Statement I is true but Statement II is false b. Statement I is false but Statement II is true c. Both Statement I and Statement II are true d. Both Statement I and Statement II are false

The correct answer is a. Statement I is true but Statement II is false According to Gauss's law, electric flux depends only on the charge... View Article

A conducting rod PQ of length 4ℓ is rotated about a point O in a uniform magnetic field B. PO = ℓ Then (a) VQ – VP = – [{Bωℓ²} / {2}] (b) VQ – VO = (5/2) Bωℓ² (c) VQ – VO = (9/2) Bωℓ² (d) VP – VQ = 4 Bωℓ²

As per the diagram Let us assume Potential difference between point O & P is VO – VP . Potential difference... View Article

A common emitter amplifier is designed with n-p-n transistor (α=0.99). The input impedence is 1kΩ and load is 10kΩ. The voltage gain will be (a) 9900 (b) 99 (c) 9.9 (d) 990

The correct answer is (d) 990 The NPN transistor consists of two n-type semiconductors that sandwich a p-type semiconductor. Here,... View Article

At low pressure, the van der Waal’s equation is reduced to

At low pressure, the van der Waal's equation is reduced to Van der Waals equation is an equation relating the relationship between the... View Article

A simple pendulum is oscillating without damping. When the displacement of the bob is less than maximum, its acceleration vector a is correctly shown in

To find the acceleration of the pendulum, firstly calculate the time taken for one oscillation (T) by the pendulum by dividing the total time by... View Article

M	T	W	T	F	S	S
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