Sample Questions - Chapter 8

Molecular Structure &
Chemical Bonding Theories

Examples of
Multiple Choice Questions

Choose the molecule that is incorrectly matched with the electronic geometry about the central atom.; (a) CF₄ - tetrahedral; (b) BeBr₂ - linear; (c) H₂O - tetrahedral; (d) NH₃ - tetrahedral; (e) PF₃ - pyramidal
2.: Choose the species that is incorrectly matched with the electronic geometry about the central atom.; (a) NO₂^- - trigonal planar; (b) ClO₄^- - tetrahedral; (c) SO₃^2- - pyramidal; (d) ClO₃^- - tetrahedral; (e) BrO₄^- - tetrahedral
3.: Which of the following pairs of molecules and their molecular geometries is WRONG?; (a) NF₃ - trigonal planar; (b) H₂O - bent; (c) BF₃ - trigonal planar; (d) AsF₅ - trigonal bipyramidal; (e) SeF₆ - octahedral
4.: Which molecule has a linear arrangement of all component atoms?; (a) CH₄; (b) H₂O; (c) CO₂; (d) NH₃; (e) BF₃
5.: Which polyatomic ion is incorrectly matched with its ionic geometry?; (a) SiCl₆^2- - trigonal bipyramidal; (b) PH₄⁺ - tetrahedral; (c) ClO₂^- - angular; (d) NH₄⁺ - tetrahedral; (e) SO₄^2- - tetrahedral
6.: Which of the following species is planar?; (a) NH₃; (b) H₃O⁺; (c) SO₃^2-; (d) PF₃; (e) NO₃^-
7.: What kind of hybrid orbitals are utilized by the carbon atom in CF₄ molecules?; (a) sp; (b) sp²; (c) sp³; (d) sp³d; (e) sp³d²
8.: A neutral molecule having the general formula AB₃ has two unshared pair of electrons on A. What is the hybridization of A?; (a) sp; (b) sp²; (c) sp³; (d) sp³d; (e) sp³d²
9.: What hybridization is predicted for sulfur in the HSO₃^- ion?; (a) sp; (b) sp²; (c) sp³; (d) sp³d; (e) sp³d²
10.: Which of the following four molecules are polar: PH₃ OF₂ HF SO₃?; (a) all except SO₃; (b) only HF; (c) only HF and OF₂; (d) none of these; (e) all of these
11.: Which molecule is nonpolar?; (a) H₂Se; (b) BeH₂; (c) PF₃; (d) CHCl₃; (e) SO₂
12.: The F-S-F bond angles in SF₆ are ______.; (a) 109^o28'; (b) 120^o only; (c) 90^o and 120^o; (d) 45^o and 90^o; (e) 90^o and 180^o
13.: Which response contains all of the characteristics listed that should apply to phosphorus trichloride, PCl₃, and no other characteristics?; (1) trigonal planar; (2) one unshared pair of electrons on P; (3) sp² hybridized at P; (4) polar molecule; (5) polar bonds; (a) 1, 4, 5; (b) 2, 3, 4; (c) 1, 2, 4; (d) 2, 4, 5; (e) another combination
14.: A (pi) bond is the result of the; (a) overlap of two s orbitals.; (b) overlap of an s and a p orbital.; (c) overlap of two p orbitals along their axes.; (d) sidewise overlap of two parallel p orbitals.; (e) sidewise overlap of two s orbitals.
15.: A triple bond contains ___ sigma bond(s) and ___ pi bond(s).; (a) 0, 3; (b) 3, 0; (c) 2, 1; (d) 1, 2; (e) 3, 2
16.: The perchloric acid molecule contains:; (a) 13 lone pairs, 1 bond, and 4 bonds.; (b) 9 lone pairs, no bonds, and 6 bonds.; (c) 8 lone pairs, 2 bonds, and 7 bonds.; (d) 2 lone pairs, 3 bonds, and 4 bonds.; (e) 11 lone pairs, no bonds, and 5 bonds.
17.: Draw a complete line-bond or electron-dot formula for acetic acid and then decide which statement is incorrect.; (a) One carbon is described by sp² hybridization.; (b) The molecule contains only one bond.; (c) The molecule contains four lone pairs of valence electrons.; (d) One carbon is described by sp³ hybridization.; (e) Both oxygens are described by sp³ hybridization.

Answers:

1. (e) 2. (c) 3. (a) 4. (c) 5. (a) 6. (e) 7. (c) 8. (d) 9. (c) 10. (a) 11. (b) 12. (e) 13. (d) 14. (d) 15. (d) 16. (e) 17. (e)

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