Practice Questions

Q32.According to molecular orbital theory, which of the following molecule will not be available? (1) H2−2 (2) He2+2 (3) He+2 (4) H−2

Q32.Which of the following statements is false? (1) Splitting of spectral lines in electrical field is (2) Frequency of emitted radiation from a black body called Stark effect goes from a higher wavelength to lower wavelength as the temperature increases (3) Photon has momentum as well as wavelength (4) Rydberg constant has unit of energy

Q32.Ejection of the photoelectron from metal in the photoelectric effect experiment can be stopped by applying 0. 5 V , when the radiation of 250 nm is used. The work function of the metal is (1) 4 eV (2) 5. 5 eV (3) 4. 5 eV (4) 5 eV

Q32.Ejection of the photoelectron from metal in the photoelectric effect experiment can be stopped by applying 0.5 V when the radiation of 250 nm is used. The work function of the metal is : (1) 4 eV (2) 5.5 eV (3) 4.5 eV (4) 5 eV

Q32.The de-Broglie's wavelength of electron present in first Bohr orbit of ' H ' atom is: (1) 4 × 0.529Å (2) 2π × 0.529Å (3) 0.529 Å (4) 0.529Å 2π

Q33.For Na+, Mg2+, F− and O2− ; the correct order of increasing Ionic radii is : (1) O2−< F−< Na+ < Mg2+ (2) Na+ < Mg2+ < F−< O2− (3) Mg2+ < Na+ < F−< O2− (4) Mg2+ < O2−< Na+ < F−

Q33.Which of the following conversions involves change in both shape and hybridisation? (1) H2O → H3O+ (2) BF3 →BF 4− (3) CH4 → C2H6 (4) NH3 → NH+4

Q33.The correct order of electron affinity is: (1) O > F > Cl (2) F > O > Cl (3) F > Cl > O (4) Cl > F > O JEE Main 2018 (15 Apr Shift 2 Online) JEE Main Previous Year Paper

Q33.Which of the following compounds contain(s) no covalent bond(s)? KCl, PH3, O2, B2H6, H2 SO4 JEE Main 2018 (08 Apr) JEE Main Previous Year Paper (1) KCl, B2H6 (2) KCl, B2H6, PH3 (3) KCl, H2 SO4 (4) KCl

Q33.For Na+, Mg2+, F− and O2− , the correct order of increasing ionic radii is: (1) O2−< F−< Na+ < Mg2+ (2) Na+ < Mg2+ < F−< O2− (3) Mg2+ < Na+ < F−< O2− (4) Mg2+ < O2−< Na+ < F−

Q34.In the molecular orbital diagram for the molecular ion N+2 , the number of electrons in the σ2p molecular orbital is JEE Main 2018 (15 Apr) JEE Main Previous Year Paper (1) 0 (2) 2 (3) 3 (4) 1

Q34.The most polar compound among the following is: JEE Main 2018 (16 Apr Online) JEE Main Previous Year Paper (1) (2) (3) (4)

Q34.In the molecular orbital diagram for the molecular ion, N+2 , the number of electrons in the σ2p molecular orbital is : (1) 0 (2) 2 (3) 3 (4) 1

Q34. Which of the following best describes the diagram of molecular orbital? (1) A bonding π orbital (2) A non-bonding orbital (3) An antibonding σ orbital (4) An antibonding π orbital Q35. ΔfG∘ at 500 K for substance ' S ' in liquid state and gaseous state are +100.7kcalmol−1 and +103 kcalmol−1 , respectively. Vapour pressure of liquid ' S ' at 500 K is approximately equal to: (R = 2calK−1 mol−1). (1) 100 atm (2) 1 atm (3) 10 atm (4) 0.1 atm

Q34.Total number of lone pair of electrons in I3− ion is: (1) 12 (2) 3 (3) 6 (4) 9

Q35.The incorrect geometry is represented by: (1) NF3 - trigonal planar (2) BF3 - trigonal planar (3) AsF5 - trigonal bipyramidal (4) H2O - bent

Q35.The combustion of benzene (l) gives CO2(g) and H2O(l). Given that heat of combustion of benzene at constant volume is −3263 .9 kJ mol−1 at 25°C; the heat of combustion (in kJ mol−1) of benzene at constant pressure will be (R = 8 .314 JK−1 mol−1) (1) −3267.6 (2) 4152.6 (3) −452.46 (4) 3260

Q35.Identify the pair in which the geometry of the species is T-shaped and square-pyramidal, respectively, (1) ICl−2 and ICl5. (2) IO−3 and IO2 F−2 . (3) ClF3 and IO−4 . (4) XeOF2 and XeOF4.

Q35.Identify the pair in which the geometry of the species is T-shape and square pyramidal, respectively JEE Main 2018 (15 Apr Shift 1 Online) JEE Main Previous Year Paper (1) ICl−2 and ICl5 (2) IO−3 and IO2F−2 (3) ClF3 and IO−4 (4) XeOF2 and XeOF4

Q36. In hydrogen azide, the bond orders of bonds (I) and (II) are ______. (1) I < 2, II > 2 (2) I > 2, II > 2 (3) I > 2, II < 2 (4) I < 2, II < 2

Q36. In the above compound, the bond orders of bonds (I) and (II) are: (1) (I) < 2, (II) > 2 (2) (I) > 2, (II) > 2 (3) (I) > 2, (II) < 2 (4) (I) < 2, (II) < 2

Q36.Assuming ideal gas behavior, the ratio of density of ammonia to that of hydrogen chloride at same temperature and pressure is: (Atomic weight of Cl is 35.5 u) (1) 1.46 (2) 1.64 (3) 0.46 (4) 0.64

Q36.Given (i) 2Fe2O3( s) →4Fe(s) + 3O2( g); ΔrG∘= +1487.0 kJ mol−1 (ii) 2CO(g) + O2( g) →2CO2( g); ΔrG∘= −514.4 kJ mol−1 Free energy change, ΔrG∘ for the reaction 2Fe2O3( s) + 6CO(g) →4Fe(s) + 6CO2( g) will be: (1) −112.4 kJ mol−1 (2) −56.2 kJ mol−1 (3) −208.0 kJ mol−1 (4) −168.2 kJ mol−1

Q36.Which of the following lines correctly show the temperature dependence of equilibrium constant K, for an exothermic reaction? (1) A & D (2) A & B (3) B & C (4) C & D

Q37.An aqueous solution contains 0. 10 M H2S and 0. 20 M HCl. If the equilibrium constant for the formation of HS− from H2S is 1.0 × 10−7 and that of S2− from HS− ions is 1.2 × 10−13 , then, the concentration of S2− ions in the aqueous solution is: (1) 5 × 10−19 (2) 5 × 10−8 (3) 3 × 10−20 (4) 6 × 10−21