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Polygonum type of embryo sac is? (1) 8-nucleate, 7-celled (2) 8nucleate, 8-celled (3) 7-nucleate, 7-celled (4) 4-nucleate, 3-celled

Answer: (1) 8-nucleate, 7-celled The embryo sac or female gametophyte is an oval structure present in the ovule of flowering... View Article

Acetone reacts with Grignard reagent to form (1) 3⁰ alcohol (2) 2⁰ alcohol (3) ether (4) no reaction

Answer: (1) 30 alcohol The reaction between Grignard reagent and ketone produces tertiary alcohol as a product. The reaction is... View Article

An electromagnetic wave, going through vacuum is described by E = E₀sin(kx-ωt). Which of the following is independent of wavelength? (1) k (2) ω (3) k/ω (4) kω

Answer:(3) k/ω E = E0sin(kx – ωt) In physics, the wavenumber is also known as propagation number or angular wavenumber... View Article

Current in a circuit falls from 5.0 A to 0.0 A in 0.1 s. If an average emf of 200V induced, calculate the self-inductance of the circuit.

Answer: Given parameters Intial current(I1) = 5.0 A Final current (I2) = 0 A Average emf (e) = 200 V... View Article

Common impurities present in bauxite are (1) CuO (2) ZnO (3) CaO (4) SiO₂

Answer: (4) SiO2 Bauxite is primarily a metallic mineral though it is also used as an industrial mineral. It is... View Article

What is multiple?

Answer: A multiple of a number is a number that is the product of a given number and some other... View Article

A rocket is moving in a gravity-free space with a constant acceleration of 2 ms^-2along positive x-direction (see figure). The length of a chamber inside the rocket is 4m. A ball is thrown from the left end of the chamber in positive x-direction with a speed of 0.3 m/s relative to the rocket. At the same time, another ball is thrown in negative x-direction with a speed of 0.2 ms^-1 from its right end relative to the rocket. The time in seconds when the two balls hit each other is (1) 8 (2) 3 (3) 4 (4) 5

Answer: (1) 8 The rocket moves in the direction of the left ball. For the ball thrown from the left... View Article

When current is coil changes from 5 A to 2 A in 0.1 s, an average of 50 V is produced. The self-inductance of the coil is. (1) 6H (2) 0.67H (3) 1.67H (4) 3H

Answer: (3) 1.67H Given E = 50V The inductor resists changes in current; as the current decreases, the inductor converts... View Article

Iron carbonyl, Fe(CO)₅ is __________. (1) trinuclear (2) tetranuclear (3) dinuclear (4) mononuclear

Answer: (4) mononuclear Iron carbonyl [Fe(CO)5] is a mononuclear in which one Fe atom is surrounded by five CO ligands.... View Article

Phenolphthalein indicator is used in the pH range (1) 3.2 – 4.4 (2) 4.8 – 6.0 (3) 6.8 – 8.4 (4) 8.2 – 10.0

Answer: (4) 8.2 – 10.0 Phenolphthalein is an organic compound which is used medicinally as a cathartic. It has a... View Article

In a certain region of space with volume 0.2 m³, the electric potential is found to be 5 V throughout. The magnitude of electric field in this region is (1)1 N/C (2) 5 N/C (3) Zero (4) 0.5 N/C

Answer:(3) Zero Given v = 5V(Constant) Consider the equation \(\begin{array}{l}E = -\frac{dV}{Dr}\end{array} \) For any displacement dr, the change in... View Article

How many hydrogen bonded water molecules are associated with CuSO₄.5H₂O? (1) five (2) one (3) four (4) three

Answer: (2) one In the crystal framework of the molecule, there are five water molecules, four of which are connected... View Article

SN1 reaction of alkyl halides leads to (1) retension of configuration (2) racemisation (3) inversion of configuration (4) None of these

Answer: (2) racemisation In an S N1 reaction of alkyl halide on chiral centres, there is inversion more than retention... View Article

When 22.4 litres of H2(g) is mixed with 11.2 litres of Cl2(g), each at STP, the moles of HCl(g) formed is equal to (1) 1 mol of HCl(g) (2) 2 mol of HCl(g) (4) 0.5 mol of HCl(g) (5) 1.5 mol of HCl(g)

When 22.4 litres of H<sub>2</sub>(g) is mixed with 11.2 litres of Cl<sub>2</sub>(g), each at STP, the moles of HCl(g) formed... View Article

Fluorine reacts with water to give (1) hydrogen fluoride and oxygen (2) hydrogen fluonde and ozone (3) hydrogen fluoride and oxygen fluoride (4) hydrogen fluoride, oxygen and ozone

Answer: (4) hydrogen fluoride, oxygen and ozone Fluorine reacts with water to produce oxygen and ozone. 2F2(g) + 2H2O(l) ⟶... View Article

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