Practice Questions

Q45.Air pollution that occurs in sunlight is (1) Acid rain (2) Reducing smog (3) Fog (4) Oxidising smog JEE Main 2019 (10 Apr Shift 2) JEE Main Previous Year Paper

Q45.Assertion: Ozone is destroyed by CFCs in the upper stratosphere. Reason: Ozone holes increase the amount of UV radiation reaching the earth. (1) Assertion and reason (2) The assertion is false, (3) Assertion and reason (4) Assertion and reason are correct, but the but the reason is are incorrect. are both correct, and reason is not the correct. the reason is the explanation for the correct explanation for assertion. the assertion.

Q45. K2HgI4 is 40% ionised in aqueous solution. The value of its van't Hoff factor (i) is: (1) 1.6 (2) 1.8 (3) 20 (4) 22

Q45.The ratio of number of atoms present in a simple cubic, body centered cubic and face centered cubic structure are, respectively : (1) 4 : 2 : 1 (2) 1 : 2 : 4 (3) 4 : 2 : 3 (4) 8 : 1 : 6

Q45.For an elementary chemical reaction, A2 k1 ⇄ 2A , the expression for d[A]dt is: k−1 (1) 2k1[A2] −2k−1[A]2 (2) 2k1[A2] −k−1[A]2 (3) k1[A2] + k−1[A]2 (4) k1[A2] −k−1[A]2

Q45.The one that is not a carbonate are is: (1) malachite (2) bauxite (3) calamine (4) siderite

Q45.For the solution of the gases w, x, y and z in water at 298 K, the Henry's law constants ( KH ) are 0.5, 2, 35 and 40 kbar, respectively. The correct plot for the given data is: (1) (2) (3) (4)

Q45.The molecule that has minimum or no role in the formation of photochemical smog, is: (1) N2 (2) O3 (3) H2C = O (4) NO

Q45.Consider the following reversible chemical reactions: k1 A2(g) + B2(g) ⇌2AB(g) .....(1) k2 6AB(g) ⇌3A2(g) + 3B2(g) .....(2) The relation between K1 and K2 is: (1) K2 = K 1−3 (2) K1K2 = 31 (3) K2 = K 13 (4) K1K2 = 3

Q45.Water filled in two glasses A and B gave BOD values of 10 and 20, respectively. The correct statement regarding them is (1) A is suitable for drinking, whereas B is not (2) B is more polluted than A (3) Both A and B are suitable for drinking (4) A is more polluted than B

Q46.Which primitive unit cell has unequal edge lengths (a ≠b ≠c) and all axial angles different from 90o (1) Hexagonal (2) Monoclinic (3) Triclinic (4) Tetragonal

Q46.The standard Gibbs energy for the given cell reaction in kJ mol−1 at 298 K is: Zn(s) + Cu2+(aq) ⟶Zn2+(aq) + Cu(s) , E0 = 2 V at 298 K (Faraday's constant , F = 96000 C mol−1) (1) −192 (2) 192 (3) 384 (4) −384

Q46.The haemoglobin and the gold sol are examples of (1) positively charged sols, (2) negatively and positively charged sols, respectively. (3) negatively charged sols. (4) positively and negatively charged sols, respectively.

Q46.The noble gas that does not occur in the atmosphere is; (1) Kr (2) Ne (3) Ra (4) He Q47.1 g of a non-volatile non-electrolyte solute is dissolved in 100 g of two different solvents A and B whose ∆TbA ebullioscopic constants are in the ratio of 1: 5. The ratio of the elevation in their boiling points, ∆TbB, is: (assuming they have the same molar mass) (1) 10: 1 (2) 1: 5 (3) 1: 0.2 (4) 5: 1

Q46.The correct set of species responsible for the photochemical smog is: (1) CO2, NO2, SO2 and hydrocarbons (2) NO2, O2, O3 and hydrocarbons (3) NO2, NO2 and hydrocarbons (4) NO, NO2, O3 and hydrocarbons

Q47.A gas undergoes physical adsorption on a surface and follows the given Freundlich adsorption isotherm equation x = kp0.5 m Adsorption of the gas increases with: (1) Decrease in p and increase in T (2) Increase in p and decrease in T (3) Increase in p and increase in T (4) Decrease in p and decrease in T

Q47.The correct match between Item I and Item II is: Item I Item II (A) Benzaldehyde (P) Mobile phase (B) Alumina (Q) Adsorbent (C) Acetonitrile (R) Adsorbate (1) (A) →(P); (B) →(R); (C) →(Q) (2) (A) →(R); (B) →(Q); (C) →(P) (3) (A) →(Q); (B) →(P); (C) →(R) (4) (A) →(Q); (B) →(R); (C) →(P)

Q47.Which one of the following statements regarding Henry's law is not correct? (1) Different gases have different 𝐾𝐻 (Henry's law (2) The partial pressure of the gas in vapour phase is constant) values at the same temperature proportional to the mole fraction of the gas in the solution (3) Higher the value of 𝐾𝐻 at a given pressure, (4) The value of 𝐾𝐻 increases with increase of higher is the solubility of the gas in the liquids temperature and 𝐾𝐻 is function of the nature of the gas

Q47. HF has highest boiling point among hydrogen halides, because it has: (1) lowest dissociation enthalpy (2) strongest van der Waals’ interactions (3) strongest hydrogen bonding (4) lowest ionic character

Q47.The electrolytes usually used in the electroplating of gold and silver, respectively, are: (1) [Au (NH3)2]+ and [Ag (CN)2]− (2) [Au (CN)2]− and [AgCl2]− (3) [Au (OH)4]− and [Ag (OH)2]− (4) [Au (CN)2]− and [Ag (CN)2]−

Q48.Among the following, the false statement is: (1) Latex is a colloidal solution of rubber particles (2) Tyndall effect can be used to distinguish between which are positively charged a colloidal solution and a true solution. (3) It is possible to cause artificial rain by throwing (4) Lyophilic sols can be coagulated by adding an electrified sand carrying charge opposite to the electrolyte. one on clouds from an aeroplane.

Q48.If a reaction follows the Arrhenius equation, the plot ln k vs (RT)1 gives straight line with a gradient (−y) unit. The energy required to activate the reactant is: (1) y/R unit (2) y unit (3) yR unit (4) −y unit

Q48.Among the following reactions of hydrogen with halogens, the one that requires a catalyst is: (1) H2 + Cl2 →2 HCl (2) H2 + I2 →2 HI (3) H2 + F2 →2 HF (4) H2 + Br2 →2 HBr

Q48.The aerosol is a kind of colloid in which (1) solid is dispersed in gas. (2) liquid is dispersed in water. (3) gas is dispersed in solid. (4) gas is dispersed in liquid.

Q48.The Mond process is used for the: (1) Purification of Zr and Ti (2) Purification of Ni (3) Extraction of Zn (4) Extraction of Mo