11. What type of hybridization occurs in the carbon atom of ethylene (C₂H₄)?

a) sp
b) sp²
c) sp³
d) sp³d
Answer: b) sp²

12. Which molecule contains a double bond?

a) H₂O
b) O₂
c) NH₃
d) CH₄
Answer: b) O₂

13. What is the molecular geometry of carbon dioxide (CO₂)?

a) Linear
b) Bent
c) Trigonal planar
d) Tetrahedral
Answer: a) Linear

14. Which of the following elements is the least electronegative?

a) Fluorine
b) Oxygen
c) Nitrogen
d) Sodium
Answer: d) Sodium

15. A molecule with a central atom and four surrounding atoms with no lone pairs on the central atom is expected to have which shape?

a) Trigonal pyramidal
b) Tetrahedral
c) Bent
d) Trigonal planar
Answer: b) Tetrahedral

16. Which bond is most likely to be nonpolar covalent?

a) H-F
b) C-H
c) O-H
d) N-H
Answer: b) C-H

17. What is the shape of the sulfur hexafluoride (SF₆) molecule?

a) Trigonal bipyramidal
b) Octahedral
c) Tetrahedral
d) Square planar
Answer: b) Octahedral

18. Which of the following has a bent molecular geometry?

a) BeCl₂
b) CO₂
c) SO₂
d) PCl₅
Answer: c) SO₂

19. What type of bond is found in a molecule of nitrogen (N₂)?

a) Single covalent bond
b) Double covalent bond
c) Triple covalent bond
d) Ionic bond
Answer: c) Triple covalent bond

20. In which compound is hydrogen bonding likely to occur?

a) CH₄
b) H₂S
c) HF
d) CCl₄
Answer: c) HF