Practice Questions

Q28.The potential energy curve for the H2 molecule as a function of internuclear distance is: JEE Main 2020 (05 Sep Shift 1) JEE Main Previous Year Paper (1) (2) (3) (4)

Q28.The acidic, basic and amphoteric oxides, respectively, are (1) Na2O, SO3, Al2O3 (2) Cl2O, CaO, P4O10 (3) N2O3, Li2O, Al2O3 (4) MgO, Cl2O, Al2O3

Q28.The third ionization enthalpy is minimum for: (1) Co (2) Fe (3) Ni (4) Mn

Q28.If AB4 molecule is a polar molecule, a possible geometry of AB4 is : (1) Square pyramidal (2) Tetrahedral (3) Rectangular planar (4) Square planar

Q28.The electron gain enthalpy (in kJ ) of fluorine, chlorine, bromine and iodine, respectively, are mol (1) −296, −325, −333 and −349 (2) −349, −333, −325 and −296 (3) −333, −349, −325 and −296 (4) −333, −325, −349 and −296

Q28.The increasing order of boiling points of the following compounds is : (1) I < III < IV < II (2) I < IV < II< III (3) IV < I < II < III (4) III < I < II < IV JEE Main 2020 (05 Sep Shift 2) JEE Main Previous Year Paper

Q28.The true statement amongst the following is: (1) Both ΔS and S are functions of temperature. (2) Both S and ΔS are not functions of temperature (3) S is not a function of temperature but ΔS is a function of temperature (4) S is a function of temperature but ΔS is not a function of temperature

Q28.The bond order and the magnetic characteristic of CN− are (1) 2 12 , diamagnetic (2) 3, diamagnetic (3) 3, paramagnetic (4) 2 21 , paramagnetic

Q28.The five successive ionization enthalpies of an element are 800, 2427, 3658, 35024 32824 kJ mol–1 . The number of valence electrons in the element is: (1) 5 (2) 4 (3) 3 (4) 2

Q28.The shape/structure of [XeF5]− and XeO3 F2 , respectively are : (1) pentagonal planar and trigonal bipyramidal (2) octahedral and square pyramidal (3) trigonal bipyramidal and pentagonal planar (4) trigonal bipyramidal and trigonal bipyramidal

Q28.The ionic radii of O2–, F–, Na+ and Mg2+ are in the order: (1) F– > O2– > Na+ > Mg2+ (2) O2– > F– > Na+ > Mg2+ (3) Mg2+ > Na+ > F– > O2– (4) O2– > F– > Mg2+ > Na+ JEE Main 2020 (04 Sep Shift 1) JEE Main Previous Year Paper

Q28.For the reaction Fe2 N(s) + 32 H2(g) ⇌2 Fe(s) + NH3(g) (1) Kc = Kp(RT) (2) Kc = Kp(RT)−1/2 (3) Kc = Kp(RT)1/2 (4) Kc = Kp(RT)3/2

Q28.Of the species, NO, NO+, NO2+ and NO−, the one with minimum bond strength is : (1) NO+ (2) NO (3) NO2+ (4) NO−

Q28.The reaction in which the hybridisation of the underlined atom is affected is (1) Disproportionation (2) 420 K−−H3PO2 → H2SO4 + NaCl → ¯¯ (3) H+ (4) XeF4 + SbF5 → NH3 →¯¯

Q28.Arrange the following bonds according to their average bond energies in descending order: C −Cl, C −Br, C −F, C −I (1) C −F > C −Cl > C −Br > C −I (2) C −Br > C −I > C −Cl > C −F (3) C −I > C −Br > C −Cl > C −F (4) C −Cl > C −Br > C −I > C −F

Q28.The value of Kc us 64 at 800 K for the reaction N2(g) + 3H2(g) →2 NH3 (g) The value of Kc for the following reaction is : NH3 (g) →12 N2 (g) + 23 H2 (g) (1) 1/64 (2) 8 (3) 1/4 (4) 1/8

Q29.If the magnetic moment of a di-oxygen species is 1.73 B. M., it may be (1) O−2 or O+2 . (2) O2 or O+2 . (3) O2 or O−2 . (4) O2, O−2 or O+2 .

Q29.Which one of the following graphs is not correct for ideal gas? d = Density, P = Pressure, T =Temperature JEE Main 2020 (02 Sep Shift 1) JEE Main Previous Year Paper (1) I (2) II (3) IV (4) III

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

Q29.Arrange the following solutions in the decreasing order of pOH : (A) 0. 01 MHCl (B) 0. 01 MNaOH (C) 0. 01 MCH3 COONa (D) 0. 01 MNaCl (1) (A) > (C) > (D) > (B) (2) (A) > (D) > (C) > (B) (3) (B) > (C) > (D) > (A) (4) (B) > (D) > (C) > (A)

Q29.The molecule in which hybrid MOs involve only one d-robital of the central atom is : (1) Ni(CN)4]2− (2) BrF5 (3) XeF4 (4) [CrF6]3−

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.Consider the following molecules and statements related to them: (a) (B) is more likely to be crystaline than (A) (b) (B) has higher boiling point than (A) (c) (B) dissolves more readily than (A) in water Identify the correct option from below: (1) (a) and (b) are true (2) (a) and (c) are true (3) only (a) is true (4) (b) and (c) are true

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.The compound that has the largest H–M–H bond angle (M = N, O, S, C), is : (1) H2O (2) NH3 (3) H2S (4) CH4