Chemical Bonding & Molecular Structure — 50 MCQs

1. Ionic bonds are typically formed between:

• a) Two nonmetals
• b) Metal and nonmetal ✅
• c) Two metals
• d) Noble gases

2. Which of these molecules is linear?

• a) H2O
• b) CO2 ✅
• c) NH3
• d) CH4

3. In a covalent bond, electrons are:

• a) Transferred
• b) Shared ✅
• c) Destroyed
• d) Created

4. The VSEPR formula AX2E2 corresponds to which shape?

• a) Linear
• b) Bent (angular) ✅
• c) Trigonal planar
• d) Tetrahedral

5. Which is more polar: H–F or H–Cl?

• a) H–Cl
• b) H–F ✅
• c) Equal
• d) Depends on temperature

6. Hybridisation of carbon in ethene (C2H4) is:

• a) sp3
• b) sp2 ✅
• c) sp
• d) dsp2

7. Resonance structures are used when:

• a) Single Lewis structure is adequate
• b) Electrons are delocalized ✅
• c) Ions are present
• d) Only ionic bonds exist

8. Bond order in O2 molecule (using molecular orbital theory) is:

• a) 1
• b) 2 ✅
• c) 3
• d) 0

9. Which is an intermolecular force?

• a) Covalent bond
• b) Hydrogen bonding ✅
• c) Ionic bond
• d) Metallic bond

10. Lewis structure represents:

• a) Nucleus only
• b) Valence electrons and bonds ✅
• c) Molecular orbitals
• d) Ionic lattices

11. Which molecule is nonpolar?

• a) H2O
• b) SO2
• c) CO2 ✅
• d) NH3

12. The bond angle in a perfect tetrahedral molecule is:

• a) 90°
• b) 100°
• c) 109.5° ✅
• d) 120°

13. sp hybridisation results in how many π bonds for acetylene (C2H2)?

• a) 0
• b) 1
• c) 2 ✅
• d) 3

14. A coordinate (dative) bond is formed when:

• a) Both atoms donate an electron each
• b) Bond is ionic
• c) One atom donates both electrons ✅
• d) Electrons are delocalized

15. Which has the highest bond polarity?

• a) C–H
• b) C–Cl
• c) H–F ✅
• d) C–C

16. Which of the following shows resonance?

• a) CH4
• b) NH3
• c) NO3- ✅
• d) H2

17. Metallic bonding is characterized by:

• a) Localized electrons
• b) Sea of delocalized electrons ✅
• c) Electron transfer only
• d) Covalent networks

18. Which of these molecules has trigonal planar geometry?

• a) NH3
• b) H2O
• c) BF3 ✅
• d) CH4

19. Greater electronegativity difference between two atoms generally leads to:

• a) More covalent character
• b) More ionic character ✅
• c) Metallic bonding
• d) No bond

20. The H–O–H bond angle decreases from ideal tetrahedral due to:

• a) Lone pair–bond pair repulsion ✅
• b) Bond pair–bond pair attraction
• c) Nuclear forces
• d) Temperature

21. In MO theory, bonding molecular orbitals are formed by:

• a) Destructive overlap
• b) Constructive overlap of atomic orbitals ✅
• c) Ionic interaction
• d) No overlap

22. Which species has a bond order of 0.5 in MO theory?

• a) He2+
• b) H2
• c) He2 (unstable) ✅
• d) O2

23. Which is an example of hydrogen bond acceptor?

• a) H atom bonded to C
• b) Oxygen atom with lone pairs ✅
• c) Metal cation
• d) Proton

24. BF3 is electron-deficient and acts as:

• a) Lewis base
• b) Lewis acid ✅
• c) Reducing agent
• d) Oxidizing agent

25. Which of the following molecules is polar?

• a) CO2
• b) H2O ✅
• c) BF3
• d) CCl4

26. Which orbital overlap leads to a σ bond?

• a) Head-on overlap of orbitals ✅
• b) Side-by-side overlap
• c) No overlap
• d) Magnetic overlap

27. Carbonyl group (C=O) has which type of hybridisation on carbon?

• a) sp3
• b) sp2 ✅
• c) sp
• d) dsp2

28. The strongest intermolecular force among these is:

• a) London dispersion
• b) Hydrogen bonding ✅
• c) Dipole–dipole
• d) Ionic attraction

29. Which of these has trigonal bipyramidal geometry?

• a) SF4
• b) PCl5 ✅
• c) BF3
• d) XeF4

30. Which bond is shortest?

• a) Single bond
• b) Double bond
• c) Triple bond ✅
• d) All equal

31. Which species is paramagnetic?

• a) N2
• b) O2 ✅
• c) CO
• d) H2

32. In methane, carbon is:

• a) sp3 hybridized ✅
• b) sp2 hybridized
• c) sp hybridized
• d) unhybridized

33. Formal charge helps in:

• a) Identifying best Lewis structure ✅
• b) Measuring bond strength
• c) Determining polarity only
• d) Predicting color

34. Which molecule shows sp3d hybridisation?

• a) SF6
• b) PCl5 ✅
• c) BF3
• d) CO2

35. The dipole moment of symmetrical molecules like CO2 is:

• a) Zero ✅
• b) High
• c) Variable
• d) Infinite

36. Which is true for a polar covalent bond?

• a) Electrons equally shared
• b) Unequal sharing of electrons ✅
• c) Complete transfer of electrons
• d) No bond formed

37. Which molecule has a trigonal pyramidal shape?

• a) BF3
• b) NH3 ✅
• c) CO2
• d) CH4

38. Which of the following increases with bond order?

• a) Bond strength and bond energy ✅
• b) Bond length only
• c) Ionic character
• d) No change

39. Which species has resonance stabilized structure?

• a) CH3+
• b) NO3- ✅
• c) NH4+
• d) H3O+

40. A molecule with central atom having 3 bonding pairs and 1 lone pair is:

• a) Trigonal planar
• b) Trigonal pyramidal ✅
• c) T-shaped
• d) Linear

41. Which bond has the highest bond enthalpy?

• a) C–C
• b) C–H
• c) C≡C ✅
• d) C–O

42. The shape of SF4 (AX4E) is:

• a) Seesaw ✅
• b) Square planar
• c) Tetrahedral
• d) Trigonal bipyramidal

43. Which of the following has the largest dipole moment?

• a) CCl4
• b) HCl ✅
• c) CO2
• d) BF3

44. In benzene, the C–C bonds are:

• a) Equal due to delocalization ✅
• b) Alternating long and short
• c) Pure single bonds
• d) Pure double bonds

45. The overlap of two p orbitals side-by-side forms:

• a) π bond ✅
• b) σ bond
• c) dative bond
• d) Ionic bond

46. Which is true for polar molecules?

• a) Have net dipole moment ✅
• b) Always symmetric
• c) Never interact with water
• d) Have no charges

47. In CO, the carbon atom has formal charge:

• a) +1
• b) -1 ✅
• c) 0
• d) +2

48. Which of these increases boiling point most?

• a) Smaller molecular weight
• b) Strong hydrogen bonding ✅
• c) Nonpolarity
• d) Lower surface area

49. Which molecule exhibits sp2 hybridisation at central atom?

• a) CH4
• b) C2H4 ✅
• c) C2H2
• d) NH3

50. Which is true about resonance energy?

• a) It stabilizes the molecule ✅
• b) It destabilizes the molecule
• c) No effect
• d) Causes bond breaking