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The electric field at a point is (1) always continuous (2) continuous if there is no charge at that point (3) discontinuous if there is a charge at that point (4) both (2) and (3) are correct

Answer: (4) both (2) and (3) are correct If there is no charge at a point, the electric field at that point is continuous. And if there is... View Article

Gastric digestion takes place efficiently in (1) Acidic medium (2) Alkaline medium (3) Neutral medium (4) Highly alkaline medium

Answer: (1) Acidic medium The gastric juice contains three substances; hydrochloric acid, the enzyme pepsin and mucus. It has a pH of 1 to 2... View Article

If A and B are two matrices such that AB=B and BA=A, then A²+B² is equal to (1) 2AB (2) 2BA (3) A+B (4) AB

Answer: (3) A+B Given: A and B are two matrices AB = B and BA = A A2 + B2 = AA + BB Since AB = B and BA = A A2 + B2 = A(BA) + B(AB) A2... View Article

1, 4, 18, 48, …….. missing number in the series is (1) 100 (2) 78 (3) 92 (4) 112

Answer: (1) 100 Given series: 1, 4, 18, 48, ? To find: Missing terms Solution: To determine the missing numbers in the series, we need to... View Article

Prime factors of the denominator of a rational number with the decimal expansion 44.123 are (1) 2,3 (2) 2,3,5 (3) 2,5 (4) 3,5

Answer: (3) 2, 5 Any number that can be represented in the form of p/q, such that p and q are integers and q ≠ 0 are known as rational... View Article

Is 41 a prime number?

Answer: A prime number is a positive integer having exactly two factors. If p is a prime, then its only factors are necessarily 1 and p itself.... View Article

Complete the following reaction, P₄+ NaOH + H₂O →?. Write the balanced equation.

Answer: P4 + 3NaOH + 3H2O → PH3 + 3NaH2PO2. It is a disproportionation reaction, wherein an element is simultaneously oxidised as well as... View Article

A mixture of camphor and benzoic acid can be easily separated by a) fractional distillation b) sublimation c) extraction with a solvent d) chemical method

Answer: d) chemical method Explanation: A mixture of camphor and benzoic acid can be easily separated by using an aqueous solution of sodium... View Article

When hydrogen peroxide is added to acidified potassium dichromate, the blue colour produced is due to the formation of: a) Cr₂O₃ b) CrO₅ c) CrO₃ d) Cr₂O₇^2-

Answer: b) CrO5 Explanation: When acidified potassium dichromate (orange) is oxidized, blue coloured chromium pentaoxide is produced. Here... View Article

Which of the following is ferromagnetic? a) Fe, Co, Ni b) Cu, Ag, Au c) Ca, Sr, Ba d) Zn, Cd, Hg

Answer: a)Fe, Co, Ni Explanation Few substances attract very strongly to the magnetic field, e.g. iron, cobalt, nickel, gadolinium and CrO2.... View Article

Find out the solubility of Ni(OH)₂in 0.1 M NaOH. The ionic product of Ni(OH)₂is 2×10^-15. a) 1×10^-13M b)1×10^-8M c) 2×10^-13M d)1×10⁸M

Answer: c) 2×10-13 Explanation Ni(OH)2→Ni2++ 2OH– ∴ Ksp= [Ni2+] [OH–]2 ⇒ Ksp= s × (0.1)2... View Article

Which of the following are present in a dilute aqueous solution of hydrochloric acid? a) H₃O⁺ + OH^– b) H₃O⁺ + Cl^– c) unionised HCl d) Cl^– + OH⁺

Answer: b) H3O+ + Cl– Explanation In the aqueous solution, HCl forms hydronium ions and chloride ions. HCl + H2O → H3O+ + Cl–... View Article

Which of the following is the most stable diazonium salt? a) CH₃N₂⁺X^– b) C₆H₅CH₂N₂⁺X^– c) C₆H₅N₂⁺X^– d) CH₃CH₂N₂⁺X^–

Answer:c) C6H5N2+X– Explanation Diazonium salt where Nitrogen is directly linked to the aryl group is the most stable diazonium salt due... View Article

Which of the following elements can be involved in pπ–dπ bonding? a) Nitrogen b) Carbon c) Boron d) Phosphorus

Answer:d) Phosphorus Explanation Phosphorus is present in 3rd period. It contains vacant 3d orbitals, hence, it can be involved in... View Article

CO+H₂ is known as a) producer gas b) water gas c) dry ice d) syn gas

Answer: b) water gas Explanation The mixture of CO+H2 is known as water gas or synthesis gas. Producer gas is a mixture of CO+N2. Syn gas is a... View Article

In the reaction, P₄ + NaOH + H₂O → PH₃ + NaH₂PO₂, the mole ratio of NaH₂PO₂ and PH₃ is :

Answer: 3 Explanation The balanced equation is P4 + 3NaOH + 3H2O → PH3 + 3NaH2PO2, so the mole ratio of NaH2PO2 and PH3is 3.... View Article

The osmotic pressure of a solution can be increased by : (1) increasing the number of solutes (2) increasing the volume (3) removing semipermeable membrane (4) decreasing the temperature

Answer:(1) increasing the number of solutes Explanation: Osmotic pressure is the minimum pressure that prevents the inward flow of pure solvent... View Article

An LPG cylinder contains 15 kg butane at 27℃ and 10 atm pressure. It is leaking. If its pressure decreases to 8 atm after one day, then the quantity of gas leaked is : (1) 2 kg (2) 1 kg (3) 4 kg (4) 3 kg

Answer: (4) 3 kg Explanation:For an ideal gas PV = nRT Here V1 = V2 R = Ideal gas constant and T = temperature = 27℃ n = moles and can be... View Article

The number of atoms in 0.1 mol triatomic gas is: (1) 1.806 × 10²³ (2) 6.02 × 10²² (3) 1.8 × 10²² (4) 3.6 × 10²³

Answer: (1) 1.806× 1023 Explanation: The number of atoms or molecules in one mole of a substance is represented by Avogadro's number NA =... View Article

Under the isothermal condition, a gas at 300 K expands from 0.1 L to 0.25L against a constant external pressure of 2 bar. Find the work done by the gas (given that 1L.bar = 100J) (1) 5kJ (2) -30J (3) 30J (4) 25J

Answer:(2) -30J Explanation: For isothermal expansion of gas: w = −PextΔV = −2 × (0.25−0.1) L.bar =... View Article

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