Practice Questions

Q29.The dipole moments of CCl4, CHCl3 and CH4 are in the order (1) CHCl3 < CH4 = CCl4 (2) CCl4 < CH4 < CHCl3 (3) CH4 < CCl4 < CHCl3 (4) CH4 = CCl4 < CHCl3

Q29.Match the type of interaction in column A with the distance dependence of their interaction energy in column B : A B (i) ion - ion (a) 1 r (ii) Dipole - dipole (b) 1 r2 (iii) London dispersion (c) 1 r3 (iv) 1 r6 JEE Main 2020 (02 Sep Shift 2) JEE Main Previous Year Paper (1) (i) – (b); (ii) – (d); (iii) – (c) (2) (i) – (a); (ii) – (b); (iii) – (d) (3) (i) – (a); (ii) – (b); (iii) – (c) (4) (i) – (a); (ii) – (c); (iii) – (d)

Q29.The predominant intermolecular forces present in ethyl acetate, a liquid, are: (1) London dispersion and dipole-dipole (2) hydrogen bonding and London dispersion (3) Dipole-dipole and hydrogen bonding (4) London dispersion, dipole-dipole and hydrogen bonding

Q29.In the figure shown below reactant A (represented by square) is in equilibrium with product B (represented by circle). The equilibrium constant is (approx): (1) 4 (2) 8 (3) 1 (4) 2

Q29.Among the compounds A and B with molecular formula C9H18O3, A is having higher boiling point than B. The possible structures of A and B are: JEE Main 2020 (08 Jan Shift 2) JEE Main Previous Year Paper (1) (2) (3) (4)

Q29.Dihydrogen of high purity (> 99. 95 %) is obtained through : (1) The reaction of Zn with dilute HCl. (2) The electrolysis of acidified water using Pt electrodes. (3) The electrolysis of brine solution. (4) The electrolysis of warm Ba (OH)2 solution using Ni electrrodes.

Q29.Consider the following reaction: N2O4(g) = 2 NO2(g) : ΔH0 = +58k For each of the following cases (a, b), the direction in which the equilibrium shifts is: (a) Temperature is decreased. (b) Pressure is increased by adding N2 at constant T. (1) (a) towards product, (b) towards reactant (2) (a) towards reactant, (b) towards product (3) (a) towards reactant, (b) no change (4) (a) towards product, (b) no change

Q30.Among the sulphates of alkaline earth metals, the solubilities of BeSO4 and MgSO4 in water, respectively, are : (1) poor and poor (2) high and poor (3) high and high (4) poor and high

Q30.For one mole of an ideal gas, which of these statements must be true? (a) Internal energy (U) and enthalpy (H) each depends on temperature. (b) Compressibility factor Z is not equal to 1 (c) CP, m –CV, m = R (d) dU = Cv dT for any process (1) (a) and (c) (2) (b), (c) and (d) (3) (c) and (d) (4) (a), (c) and (d)

Q30.For the following Assertion and Reason, the correct option is Assertion (A) : When Cu (II) and sulphide ions are mixed, they react together extremely quickly to give a solid. Reason (R) : The equilibrium constant of Cu2+(aq) + S2−(aq) ⇌Cus(s) is high because the solubility product is low. (1) (A) is false and (R) is true. (2) Both (A) and (R) are false. (3) Both (A) and (R) are true but (R) is not the (4) Both (A) and (R) are true and (R) is the explanation for (A). explanation for (A).

Q30.If enthalpy of atomization for Br2(l) is x kJ/mol and bond enthalpy for Br2 is y kJ/mol, the relation between them (1) is x = y. (2) does not exist. (3) is x > y. (4) is x < y.

Q30.Which one of the following compounds possesses the most acidic hydrogen? (1) (2) H3C −C ≡C −H (3) (4)

Q30.A mixture of one mole each of H2 , He and O2 each are enclosed in a cylinder of volume V at temperature T. If the partial pressure of H2 is 2 atm, the total pressure of the gases in the cylinder is: (1) 6 atm (2) 38 atm (3) 14 atm (4) 22 atm Q31. 100 mL of 0. 1 M HCl is taken in a beaker and to it 100 mL 0. 1 M NaOH of is added in steps of 2 mL and the pH is continuously measured. Which of the following graphs correctly depicts the change in pH ? (1) (2) (3) (4)

Q30.The equation that represents the water-gas shift reaction is : (1) CH4(g) + H2O(g) 1270Ni K CO(g) + 3H2(g) (2) 1273K−2C(s) + O2(g) + 4N2(g) → 2 CO(g) + 4N2(g) (3) 1270 K−C(s) + H2O(g) → CO(g) + H2(g) (4) 673K−CO(g) + H2O(g) → CO2(g) + H2(g) catalyst

Q30.Five moles of an ideal gas at 1 bar and 298 K is expanded into vacuum to double the volume. The work done is : (1) Cv(T2 −T1) (2) −RT(V2 −V1) (3) −RT ln V2/V1 (4) Zero

Q30.The relative strength of the interionic/ intermolecular forces in a decreasing order is: (1) dipole-dipole > ion-dipole > ion-ion (2) ion-dipole > ion-ion > dipole-dipole (3) ion-dipole > dipole-dipole > ion-ion (4) ion-ion > ion-dipole > dipole-dipole

Q30.The redox reaction among the following is (1) formation of ozone from atmospheric oxygen in (2) reaction of [Co(H2O)6]Cl3 with AgNO3 the presence of sunlight (3) reaction of H2SO4 with NaOH (4) combination of dinitrogen with dioxygen at 2000K

Q30.The stoichiometry and solubility product of a salt with the solubility curve given below is, respectively: (1) X2Y, 2 × 10−9M3 (2) XY2, 4 × 10−9M3 (3) XY2, 1 × 10−9M3 (4) XY, 2 × 10−6M3 JEE Main 2020 (08 Jan Shift 1) JEE Main Previous Year Paper

Q30.The molecular geometry of SF6 is octahedral. What is the geometry of SF4 (including lone pair(s) of electrons, if (any)? (1) Tetrahedral (2) Trigonal bipyramidal (3) Pyramidal (4) Square planar

Q30.For the following Assertion and Reason, the correct option is: Assertion: The pH of water increases with increase in temperature. Reason: The dissociation of water into H+ and OH− is an exothermic reaction. (1) Both assertion and reason are true, and the reason (2) Both assertion and reason are false. is the correct explanation for the assertion. (3) Both assertion and reason are true, but the reason (4) Assertion is not true, but reason is true. is not the correct explanation for the assertion.

Q30.Match the following compounds (Column-I) with their uses (Column-II) S. No. Column-I S.No. Column-II (I) Ca (OH)2 (A) casts of statues (II) NaCl (B) white wash JEE Main 2020 (06 Sep Shift 2) JEE Main Previous Year Paper (III) CaSO4 ⋅12 H2O (C) antacid (IV) CaCO3 (D) washing soda preparation (1) (I)-(D), (II)-(A), (III)-(C), (IV)-(B) (2) (I)-(B), (II)-(D), (III)-(A), (IV)-(C) (3) (I)-(B), (II)-(C), (III)-(D), (IV)-(A) (4) (I)-(D), (II)-(C), (III)-(B), (IV)-(A)

Q30.The solubility product of Cr(OH)3 at 298K is 6.0 × 10−31. The concentration of hydroxide ions in a saturated solution of Cr(OH)3 will be 4 (1) 1 1 (2.22 × 10−31) 4 (2) (18 × 10−31) (3) 12 (4) 14 (18 × 10−31) (4.86 × 10−29) Q31. 5g of zinc is treated separately with an excess of (a) dilute hydrochloric acid and (b) aqueous sodium hydroxide. The ratio of the volumes of H2 evolved in these two reactions is: (1) 1 : 2 (2) 1 : 1 (3) 1 : 4 (4) 2 : 1

Q30.Lattice enthalpy and enthalpy of solution of NaCl are 788 kJmol−1and 4kJmol −1, respectively. The hydration enthalpy of NaCl is: (1) −780 kJmol−1 (2) 780 kJmol−1 (3) −784 kJmol−1 (4) 784 kJmol−1

Q31.The increasing order of the acidity of the α-hydrogen of the following compounds is: (A) (B) (C) (D) (1) (D) < (C) < (A) < (B) (2) (B) < (C) < (A) < (D) (3) (A) < (C) < (D) < (B) (4) (C) < (A) < (B) < (D)

Q31.On combustion of Li, Na and K in excess of air, the major oxides formed, respectively, are: (1) Li2 O2, Na2 O and K2O2 (2) Li2 O, Na2 O2 and KO2 (3) Li2 O, Na2 O and K2O2 (4) Li2 O, Na2 O2 and K2O