Chemical Bonding Exercise 5

CHEMICAL BONDING EXERCISE #5 1. The bond order in NO is 2.5 while that in NO+ is 3. Which of the following statement is true for these two species? [AIEEE–2004] + (A) Bond length in NO is equal to that NO (B) Bond length in NO is greater than NO+ (C) Bond length in NO+ is greater than NO (D) Bond length is unpredictable 2. The states of hybridization of boron and oxygen atoms in boric acid (H3BO3) are respectively: [AIEEE 2004] 3 2 2 3 2 2 3 (A) sp and sp (B) sp and sp (C) sp and sp (D) sp and sp3 3. The maximum number of 90º angles between bond pair-bond pair of electrons is observed in: [AIEEE 2004] 2 3 3 3 2 (A) dsp hybridization (B) sp d hybridization (C) dsp hybridization (D) sp d hybridization 4. Which one of the following specie is diamagnetic in nature? (A) He2+ (B) H2 (C) H2+ [AIEEE-2005] (D) H2 – 5. Which of the following molecule\ion does not contain unpaired electrons? [AIEEE-2006] + 2– (A) N2 (B) O2 (C) O2 (D) B2 6. Among the following mixtures, dipole-dipole as the major interaction, is present in: [AIEEE-2006] (A) KCl and water (B) benzene and carbon tetrachloride (C) benzene and ethanol (D) acetonitrile and acetone 7. A metal, M forms chlorides in its +2 and +4 oxidation states. Which of the following statement about these chlorides is correct? [AIEEE-2006] (A) MCl2 is more ionic than MCl4 (B) MCl2 is more easily hydrolysed than MCl4 (C) MCl2 is more volatile than MCl4 (D) MCl2 is more soluble in anhydrous ethanol than MCl4 8. The decreasing values of bond angles from NH3 (106º) to SbH3 (91º) down group-15 of the periodic table is due to: [AIEEE-2006] (A) decreasing lp – bp repulsion (B) increasing electronegativity (C) increasing bp – bp repulsion (D) increasing p-orbital character in sp3 9. In which of the following ionization process, the bond order has increased and the magnetic behaviour has changed: [AIEEE-2007] + + + (A) NO → NO (B) O2 → O2 (C) N2 → N2 (D) C2 → C2+ 10. Which of the following species exhibits the diamagnetic behaviour: (A) O2+ (B) O2 (C) NO (D) O2 Which one of the following pairs of species have the same bond order? (A) CN– and NO+ (B) CN– and CN+ (C) O2– and CN– [AIEEE-2008] (D) NO+ and CN+ 11. [AIEEE-2007] 2– CHEMICAL BONDING 12. The bond dissociation energy of B–F in BF3 is 646 kJ mol–1 whereas that of C–F in CF4 is 515 kJ mol–1. The correct reason for higher B–F bond dissociation energy as compared to that of C–F is: [AIEEE-2009] (A) Significant p – p interaction between B and F in BF3 whereas there is not possibility of such interaction between C and F in CF4. (B) Lower degree of p – p interaction between B and F in BF3 than that between C and F in CF4 (C) Smaller size of B-atom as compared to that of C-atom (D) Stronger  bond between B and F in BF3 as compared to that between C and F in CF4 13. Using MO theory predict which of the following species has the shortest bond length? [AIEEE-2009] – 2– 2+ + (A) O2 (B) O2 (C) O2 (D) O2 14. Among the following the maximum covalent character is shown by the compound: [AIEEE-2011] (A) AlCl3 (B) MgCl2 (C) FeCl2 (D) SnCl2 15. Which one of the following molecules is expected to exhibit diamagnetic behaviour? [AIEEE-2013] (A) C2 (B) N2 (C) O2 (D) S2 In which of the following pairs of molecules/ions, both the species are not likely to exist? [JEE-M-2013] + 2– – 2– 2+ – (A) H2 , He2 (B) H2 , He2 (C) H2 , He (D) H2 , He22+ 16. 17. Stability of the species Li2, Li2– and 2 Li2+ increases in the order of: [JEE-M-2013] + – – + – + – (A) Li2 < Li2 < Li2 (B) Li2 < Li2 < Li2 (C) Li2 < Li2 < 2 Li2 (D) Li2 < Li2 < Li2+ 18. Which one of the following properties is not shown by NO? (A) It combines with oxygen to form nitrogen dioxide (B) It's bond order is 2.5 (C) It is diamagnetic in gaseous state (D) It is a neutral oxide 19. The correct order of thermal stability of hydroxides is: (A) Ba(OH)2 < Sr(OH)2 < Ca(OH)2 < Mg(OH)2 (B) Mg(OH)2 < Sr(OH)2 < Ca(OH)2 < Ba(OH)2 (C) Mg(OH)2 < Ca(OH)2 < Sr(OH)2 < Ba(OH)2 (D) Ba(OH)2 < Ca(OH)2 < Sr(OH)2 < Mg(OH)2 20. Which of the alkaline earth metal halides given below is essentially covalent in nature: [JEE-M-2015 (on line)] (A) SrCl2 (B) CaCl2 (C) BeCl2 (D) MgCl2 21. Which one of the following alkaline earth metal sulphates has its hydration enthalpy greater than its lattice enthalpy? [JEE-M-2015] (A) BaSO4 (B) SrSO4 (C) CaSO4 (D) BeSO4 [JEE-M-2014] [JEE-M-2015 (on line)] CHEMICAL BONDING 22. The intermolecular interaction that is dependent on the inverse cube of distance between the molecules is: [JEE-M-2015] (A) London force (B) Hydrogen bond (C) ion-ion interaction (D) ion-dipole interaction 23. Which one has the highest boiling point? (A) Kr (B) Xe [JEE-M-2015] (C) He (D) Ne 24. Which intermolecular force is most responsible in allowing xenon gas to liquefy? [JEE (MAIN) ONLINE 2016] (A) Ionic (B) Instantaneous dipole- induced dipole (C) Dipole - dipole (D) Ion - dipole 25. The bond angle H–X–H is the greatest in the compound: (A) NH3 (B) H2O (C) PH3 [JEE (MAIN) ONLINE 2016] (D) CH4 26. Which of the following species is not paramagnetic? (A) NO (B) CO (C) O2 [JEE (MAIN) ONLINE 2017] (D) B2 27. Which of the following is paramagnetic? (A) CO (B) O22– (C) NO+ [JEE-MAIN-2017 (ONLINE)] (D) B2 (C) PF5 [JEE-MAIN-2017 (On-line)] (D) SF6 28. sp3d2 hybridization is not displayed by: (A) [CrF6]3– (B) BrF5 29. The number of S=O and S–OH bonds present in peroxodisulphuric acid and pyrosulphuric acid respectively are: [JEE-MAIN-2017 (On-line)] (A) (2 and 4) and (2 and 4) (B) (4 and 2) and (2 and 4) (C) (2 and 2) and (2 and 2) (D) (4 and 2) and (4 and 2) 30. The correct sequence of decreasing number of -bonds in the structures of H2SO3, H2SO4 and H2S2O7 is: [JEE-MAIN-2017 (On-line)] (A) H2S2O7 > H2SO4 > H2SO3 (B) H2SO3 > H2SO4 > H2S2O7 (C) H2S2O7 > H2SO3 > H2SO4 (D) H2SO4 > H2S2O7 > H2SO3 31. The increasing order of the boiling point for the following compounds is: (I) C2H5OH (II) C2H5Cl (A) (III) < (II) < (I) < (IV) (C) (IV) < (III) < (I) < (II) 32. [JEE-MAIN-2017 (On-line)] (III) C2H5CH3 (IV) C2H5OCH3 (B) (II) < (III) < (IV) < (I) (D) (III) < (IV) < (II) < (I) The number of P–OH bonds and the oxidation state of phosphorus atom in pyrophosphoric acid (H4P2O7) respectively are: [JEE-MAIN-2017 (On-line)] (A) five and four (B) five and five (C) four and five (D) four and four CHEMICAL BONDING 33. The group having triangular planar structures is: (A) CO32–, NO3–, SO3 (C) NH3, SO3, CO32– [JEE-MAIN-2017 (On-line)] (B) NCl3, BCl3, SO3 (D) BF3, NF3, CO32– 34. In the molecular orbital diagram for the molecular ion, N2+, the number of electrons in the 2p molecular orbitals: [JEE Main online - 2018] (A) 0 (B) 1 (C) 2 (D) 3 35. Which of following is a Lewis acid? (A) PH3 (B) B(CH3)3 (C) NaH [JEE Main online - 2018] (D) NF3 36. (I) (II) H—N---N---N In hydrogen azide (above) the bond orders of bonds (I) and (II) are: (I) (II) (A) <2 >2 (B) >2 <2 (C) >2 >2 (D) <2 <2 37. The decreasing order of bond angles in BF3, NH3, PF3 and I3– is: [JEE Main online - 2018] – – (A) I3 > NH3 > PF3 > BF3 (B) I3 > BF3 > NH3 > PF3 – (C) BF3 > I3 > PF3 > NH3 (D) BF3 > NH3 > PF3 > I3– 38. Xenon hexafluoride on partial hydrolysis produces compounds ‘X’ and ‘Y’. Compounds ’X’ and ‘Y’ and the oxidation state of Xe are respectively: [JEE Main online - 2018] (A) XeO2(+4) and XeO3(+6 (B) XeOF4(+6) AND XeO3(+6) (C) XeO2F2(+6) and XeO2(+4) (D) XeOF4(+6) and XeO2F2(+6) 39. Among the oxides of nitrogen: N2O3, N2O4 and N2O5; the molecule(s) having nitrogen-nitrogen bond is/are: [JEE Main online - 2018] (A) Only N2O5 (B) N2O3 and N2O5 (C) N2O5 and N2O5 (D) N2O3 and N2O4 40. Which of the following conversions involves change in both shape and hybridisation? [JEE Main online - 2018] + + (A) NH3 → NH4 (B) CH4 → C2H6 (C) H2O → H3O (D) BF3 → BF4– 41. A group 13 element ‘X’ reacts with chlorine gas to produce a compound XCl 3 is electron deficient and easily reacts with NH3 to form Cl3X  NH3 adduct; however, XCl3 does not dimerize. X is: [JEE Main online - 2018] (A) B (B) Al (C) Ga (D) In 42. Which of the following best describes the diagram below of a molecular orbital? [JEE Main online - 2018] (A) A non-bonding orbital (C) A bonding  orbital [JEE Main online - 2018] (B) An antibonding  orbital (D) An antibonding  orbital