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Sansad TV Perspective: Budget 2022-23: Economic lifelines in focus’

In the series Sansad TV Perspective, we bring you an analysis of the discussion featured on the insightful programme ‘Perspective’ on Sansad TV,... View Article

31 Jan 2022: The Hindu Analysis

UPSC Current Affairs Preparation: The Hindu Analysis Watch expert analysis of ‘The Hindu’ dated 31 Jan 2022. Important news and views to boost... View Article

consider-the-bcc-unit-cells-of-the-solids-1-and-2-with-the-position-of-atoms-as-shown-below-the-radius-of-atom-b-is-twice-that-of-atom-a-the-unit-cell-edge-length-is-50-more-in-solid-2-than-in-1-what-is-the-approximate-packing-efficiency-in-solid-2

Image (A) 45 % (B) 65 % (C) 75 % (D) 90 % The Correct Answer is (D) 90 % Solution: Given: r_{B} = 2r_{A} The packing fraction for Solid... View Article

csbr-crystallises-in-a-body-centred-cubic-lattice-the-unit-cell-length-is-4366-pm-given-that-the-atomic-mass-of-cs-is-133-br-is-80-amu-and-avogadro-number-is-602-1023-mol-1-what-will-be-the-density-of-csbr

(A) 8.5 g/cm3 (B) 4.25 g/cm3 (C) 42.5 g/cm3 (D) 0.425 g/cm3 The Correct Answer is (A) 8.5 g/cm3. Solution: As we know, Denisty = \frac{Z... View Article

assertion-through-the-central-atom-of-both-nh3-and-h2o-molecules-are-sp3c-hybridised-yet-the-h-n-h-bond-angle-is-greater-than-that-of-h-o-hreason-this-is-because-the-nitrogen-atom-has-a-lone-pair-and-the-oxygen-atom-has-two-lone-pairs

(A) Assertion is true, but Reason is false. (B) Both Assertion and Reason are false. (C) Both Assertion and Reason are true. The Reason is the... View Article

Consider the following statements: 1. Cs+ is more highly hydrated than the other alkali metal ions.2. Lithium has the highest melting point among the alkali metals Li, Na, K, and Rb.3. Only lithium forms a stable nitride by direct combination among the alkali metals.Which of these statements are correct.

(A) 1 and 2 are correct (B) 2 and 3 are correct (C) 1 and 3 are correct (D) 1, 2 and 3 are correct The Correct Answer is (B) 2 and 3 are... View Article

Oxygen is prepared by catalytic decomposition of potassium chlorine (KClO_(3)). Decomposition of potassium, chloride gives potassium chloride (KCl) and oxygen (O_(2)). How many moles and how many grams of KClO_(3) are required to produce 2.4 mole O_(2)?

Decomposition of KClO3 takes places as, 2KClO3(s) → 2KCl(s) + 3O2(g) 2 mole of KClO3 ≡ 3mole of O2 3 mole O2 formed by 2 mole KClO3 2.4 mole O2... View Article

For a saturated solution of AgCl at 25^(@)C, specific conductance is 3.41xx10^(-6)ohm^(-1) cm^(-1) and that of water used for preparing the solution is 1.60xx10^(-6)ohm^(-1)cm^(-1). If lamda_(AgCl)^(o)=138.3ohm^(-1)cm^(2)eq^(-1), the K_(sp) of AgCl is 0.17xx10^(-x)M^(2). The value of x is

For AgCl molarity = normalityk = 3.41×10−6−1.60×10−6 = 1.81×10−6Ω−1cm−1For saturated... View Article

What is observed when silver nitrate solution is added to potassium iodide solution,the precipitated silver iodide adsorbs iodide ions from the dispersion medium and negatively charged colloidal sol results. However, when KI solution is added to AgNO3 solution, positively charged sol results due to adsorption of Ag + ions from dispersion medium.

(A) AgI/I+ (B) AgI/Ag– (C) AgI/I- K+ (D) AgI/Ag+I- The Correct Answer is (A) AgI/I+ Explore more such questions and answers at BYJU'S.... View Article

N_{2} + O_{2} rightleftharpoons 2NO + Heat.In the above given chemical reaction, which of the following conditions is suitable to get a good yield of NO?

(A) Increase in pressure (B) Decrease in pressure (C) Increase in temperature (D) Decrease in temperature The Correct Answer is (C)... View Article

(I) The radius of an anion is larger than that of the parent atom. (II) The I.E. increases from left to right in a period generally (III) The electronegativity of an element is the tendency of an isolated atom to attract an electron. Which of the above-given statement are correct?

(A) (I) (B) (II) (C) (III) (D) All Of These The Correct Answer is (D) All Of These. Explore more such questions and answers at BYJU'S.... View Article

For an ideal binary liquid solution with P0A > P0B which relation between XA (mole fraction of A in liquid phase) and YA (mole fraction of A in vapour phase) is correct, XB and YB are mole fractions of B in liquid and vapour phase respectively:

(A) XA = YA (B) XA > YA (C) XA < YA (D) The Correct Answer is (D) Solution: Therefore, Since, Therefore, Explore... View Article

Consider the bcc unit cells of the solids 1 and 2 with the position of atoms as shown below. The radius of atom B is twice that of atom A. The unit cell edge length is 50% more in solid 2 than in 1. What is the approximate packing efficiency in solid 2?

(A) 45 % (B) 65 % (C) 75 % (D) 90 % The Correct Answer is (D) 90 % Solution: Given: r_{B} = 2r_{A} The packing fraction for Solid 2 is :... View Article

CsBr crystallises in a body-centred cubic lattice. The unit cell length is 436.6 pm. Given that the atomic mass of Cs is 133, Br is 80 amu and Avogadro number is 6.02 * 1023 mol-1. What will be the density of CsBr?

(A) 8.5 g/cm3 (B) 4.25 g/cm3 (C) 42.5 g/cm3 (D) 0.425 g/cm3 The Correct Answer is (A) 8.5 g/cm3. Solution: As we know, Denisty = Given:... View Article

in radioactive decay process, the negatively charged emitted β-particles are (a) the electrons produced as a result of the decay of neutrons inside the nucleus (b) the electrons produced as a result of collisions between atoms (c) the electrons orbiting around the nucleus (d) the electrons present inside the nucleus.

Solution: (A) The electrons produced as a result of the decay of neutrons inside the nucleus Beta decay is the radioactive decay where an... View Article

Assertion: Through the central atom of both NH3 and H2O molecules are sp3C hybridised, yet the H-N-H bond angle is greater than that of H-O-H.Reason: This is because the nitrogen atom has a lone pair and the oxygen atom has two lone pairs.