1. Which of the following molecules does
not have a polar covalent bond?
a) CH4
b) H2O
c) CH3OH
d) Cl2

2. Which of the following molecules is a
dipole?
a) HBr
b) CH4
c) H2
d) CO2

3. Which of the following has bonding that
is ionic?
a) H2
b) MgF2
c) H2O
d) CH4

4. Which of the following is a correct Lewis
structure?
: Cl :
a) : O : C : O : b) : Cl : C : Cl :
c) Cl : : Cl d) : N : N :

5. Which of the following is an incorrect
Lewis structure?
a) H : N : H b) : O : H H
c) H : C : H d) : N : : : N :

6. The correct Lewis structure for SO2?
a) : O : S : O : b) : O : S : : O :
c) : O : : S : : O : d) : O : S : O :

7. Carbon dioxide, CO2, is a nonpolar molecule because
Oxygen is more electronegative than carbon
The two oxygen atoms are bonded to the carbon
atom
The molecule has a linear structure with the
carbon atom in the middle
d) The carbon-oxygen bonds are polar covalent

8. When a magnesium atom participates in a
chemical reaction, it is most likely to
a) lose 1 electron
b) gain 1 electron
c) lose 2 electrons
d) gain 2 electrons

9. If X represents an element of Group IIIA,
what is the general formula for its oxide?
a) X3O4
b) X3O2
c) XO
d) X2O3

10. Which of the following has the same
electron structure as an argon atom?
a) Ca2+
b) Cl0
c) Na+
d) K0

11. As the difference in electronegativity
between two elements decreases, the
tendency for the elements to form a
covalent bond
Increases
Decreases
Remains the same
Sometimes increases & sometimes decreases

12. Which compound forms a tetrahedral
molecule?
NaCl
CO2
CH4
MgCl2

13. Which compound has a bent (V-shaped)
molecular structure?
NaCl
CO2
CH4
H2O H O: H

14. Which compound has double bonds
within its molecular structure?
NaCl
CO2 O=C=O
CH4
H2O

15. The total number of valence electrons in a
nitrate ion? 12 18 23 24

16. The number of electrons in a triple bond is3 4 6 8

17. The number of unbonded pairs of electrons
in H2O is
a) 0
b) 1
c) 2
d) 4

18. Which of the following does not have a
noble gas configuration? Na
Sc3+ Ar
O2-