Chapter 9: (2 points each)
1. Which one of the following is most likely to be an ionic compound?
A) CaCl2 B) CO2 C) CS2 D) SO2 E) OF2
2. Which one of the following is most likely to be an ionic compound?
A) ClF3 B) FeCl3 C) NH3 D) PF3 E) SO3
3. Which one of the following is most likely to be an ionic compound?
A) NCl3 B) BaCl2 C) CO D) SO2 E) SF4
4. Which of the following pairs of elements would be most likely to form an ionic
compound?
A) Cl and I B) Al and K C) Cl and Mg D) C and S E) Al and Mg
5. Which one of the following is most likely to be a covalent compound?
A) Rb2O B) BaO C) SrO D) SeO2 E) MnO2
6. Which one of the following is most likely to be a covalent compound?
A) KF B) CaCl2 C) SF4 D) Al2O3 E) CaSO4
7. Which one of the following is most likely to be a covalent compound?
A) CsOH B) NF3 C) Sr(NO3)2 D) CaO E) LiF
8. The Lewis dot symbol for the a lead atom is

A)


Pb :
B) Pb 


D) : Pb 
C) Pb 



E) Pb 
9. The Lewis dot symbol for the S 2– ion is

A) : S :


B) : S : 2–

C) S2–

D)  S  2–


E) : S 

10. The Lewis dot symbol for the chloride ion is

A) : Cl 


B) : Cl : –

C) : Cl –

D) : Cl : – E) Cl–

11. The Lewis dot symbol for the calcium ion is
A) : Ca : 2+
B) Ca

C) : Ca : 2+

D) Ca2+
E) Ca
12. Which one of the following ionic solids would have the largest lattice energy?
A) NaCl B) NaF C) CaBr2 D) CsI E) CaCl2
13. Which of the following ionic solids would have the largest lattice energy?
A) SrO B) NaF C) CaBr2 D) CsI E) BaSO4
Page 161
Chapter 9: Chemical Bonding I: Basic Concepts
14. Which of the following ionic solids would have the largest lattice energy?
A) KF B) KI C) LiF D) LiI E) NaF
15. Which of the elements listed below has the greatest electronegativity?
A) Na B) As C) Ga D) Cs E) Sb
16. Which of the atoms listed below is the most electronegative?
A) Li B) Cs C) P D) As E) Ge
17. Which of the elements listed below has the greatest electronegativity?
A) Se B) Sb C) K D) Ga E) Fe
18. Which of the elements listed below is the least electronegative?
A) Sr B) V C) Ni D) P E) I
19. Which of the elements listed below has the greatest electronegativity?
A) Mg B) Ga C) Si D) Ba E) Pb
20. A polar covalent bond would form in which one of the following pairs of atoms?
A) Cl  Cl B) Si  Si C) Ca  Cl D) Cr  Br E) P  Cl
21. What type of chemical bond holds the atoms together within a water molecule?
A) Ionic bond
C) Polar covalent bond
B) Nonpolar covalent bond
D) Coordinate covalent bond
22. Classify the C  Cl bond in CCl4 as ionic, polar covalent, or nonpolar covalent.
A) ionic B) polar covalent C) nonpolar covalent
23. Classify the Ca  Cl bond in CaCl2 as ionic, polar covalent, or nonpolar covalent.
A) ionic B) polar covalent C) nonpolar covalent
24. The electron dot formula for O2 shows
A) a single covalent bond
B) a double covalent bond
C) an ionic bond
D)
E)
a total of 8 x 2 = 16 electron dots
a total of 32 electron dots
25. The number of lone electron pairs in the N2 molecule is ___.
A) 1 B) 2 C) 3 D) 4 E) 5
26. The number of lone electron pairs in the NO2– ion is ___.
A) 4 B) 5 C) 6 D) 7 E) 8
27. The number of lone electron pairs in the CO32– ion is ___.
A) 4 B) 5 C) 6 D) 7 E) 8
Page 162
Chapter 9: Chemical Bonding I: Basic Concepts
28. The total number of bonding electrons in a molecule of formaldehyde (H2CO) is
A) 3 B) 4 C) 6 D) 8 E) 18
29. The Lewis structure for CS2 is:






A) C  S S






B) : S C S :




C) S  C  S



D) S  C S :


30. Which of the following Lewis structures is incorrect?
A)
D)
B)
E)
C)
31. What is the formal charge on the oxygen atom in N2O (the atomic order is N–N–O)?
A) 0 B) +1 C) –1 D) –2 E) +2
32. Which of the following substances will display an incomplete octet in its Lewis
structure?
A) CO2 B) Cl2 C) ICl D) NO E) SO2
33. Which of the elements listed below is most likely to exhibit an expanded octet in its
compounds?
A) O B) S C) Na D) C E) N
34. Which one of the following compounds does not follow the octet rule?
A) NF3 B) CF4 C) PF5 D) AsH3 E) HCl
35. Which one of the following compounds does not follow the octet rule?
A) NF3 B) CO2 C) CF4 D) Br2 E) NO
36. Which response includes all the molecules below that do not follow the octet rule?
(1) H2S (2) BCl3 (3) PH3 (4) SF4
A) (2) and (4) B) (2) and (3) C) (1) and (2) D) (3) and (4) E) (1) and (4)
37. Which one of the following molecules has an atom with an incomplete octet?
A) NF3 B) H2O C) AsCl3 D) GeH4 E) BF3
Page 163
Chapter 9: Chemical Bonding I: Basic Concepts
38. Which one of the following molecules has an atom with an expanded octet?
A) HCl B) AsCl5 C) ICl D) NCl3 E) Cl2
39. Which molecule has a Lewis structure that does not obey the octet rule?
A) N2O B) CS2 C) PH3 D) CCl4 E) NO2
40. Write the Lewis dot symbol for the chloride ion.
41. Write the Lewis dot symbol for the sulfide ion.
42. Write a Lewis structure for OF2.
43. Write a Lewis structure for the nitrate ion, NO3–, showing all non-zero formal charges.
44. Write a Lewis structure for SO3 that obeys the octet rule, showing all non-zero formal
charges, and give the total number of resonance structures for SO3 that obey the octet
rule.
45. Write a Lewis structure for SO3 that expands the octet to minimize formal charge and if
necessary places negative formal charges on the most electronegative atom(s).
46. Write the Lewis structure of boron trifluoride.
47. Write the Lewis structure of ammonia (nitrogen trihydride).
48. Which of the following solids would have the highest melting point?
A) NaF B) NaCl C) NaBr D) NaI
49. Which of the following solids would have the highest melting point?
A) NaI B) NaF C) MgO D) MgCl2 E) KF
50. Which of the following solids would have the lowest melting point?
A) KI B) KBr C) KCl D) KF
Page 164