Honors Chemistry
Unit 4 Sample Problems (Key)
Page 1 of 5
These are typical questions similar to (or, maybe even the same as) those that will be used on the first semester exam.
1. Aluminum has _______ valence electrons.
d. 3
2.
I.
II.
III.
IV.
Main group elements include _______.
s-block
p-block
d-block
f-block
a. I and II
3. Sulfur has _______ pairs of valence electrons.
c. 3
4. Iodine has _______ unpaired valence electrons.
a. 1
5. Neon has _______ valence electrons.
d. 8
6. Sodium has _______ unpaired valence electrons.
a. 1
7. Magnesium has _______ valence electrons.
a. 2
8. Gallium has _______ valence electrons.
d. 3
9. Selenium has _______ pairs of valence electrons.
c. 3
10. Fluorine has _______ unpaired valence electrons.
a. 1
11. Helium has _______ valence electrons.
a. 2
12. All Group 14 elements have _______ valence electrons.
c. 4
13. All Group 15 elements have _______ valence electrons.
b. 5
14. The electrons involved in the formation of a chemical
bond are called ...
d. valence electrons.
15. A chemical bond resulting from the electrostatic attraction
between positive ions and negative ions is called a(n) ...
b. ionic bond.
16. The chemical bond formed when two atoms share
electrons is called a(n) ...
a. covalent bond.
17. If two covalently bonded atoms are identical, the bond is
c. nonpolar covalent.
18. The greater the electronegativity difference between two
bonded atoms, the greater the likelihood that the bond will
be ...
b. ionic.
21. A neutral group of atoms held together by covalent bonds
is a ...
c. molecule.
22. What is the Lewis structure for hydrogen chloride, HCl?
..
..
A. Cl−H:
B. :H−Cl:
C. :H−Cl:
D. H−Cl:
..
..
d. D
24. The model for predicting the shape of a molecule that is
based on the repulsion of electron pairs for each other is
called ...
c. VSEPR theory.
25. The strongest bonds are ______ bonds.
a. covalent network
26. The weakest bonds are ______ bonds.
d. covalent.
27. ____________ is an example of an extended covalent
network.
d. Diamond
28. ____________ is an example of an extended covalent
network.
a. Quartz (silicon dioxide)
29. The 3-dimensional structure of CCl4 is ...
e. tetrahedral.
30. The 3-dimensional structure of F2 is ...
a. linear.
31. The 3-dimensional structure of HCN is ...
a. linear.
32. The 3-dimensional structure of H2S is ...
b. bent.
33. The 3-dimensional structure of HBr is ...
a. linear.
34. The 3-dimensional structure of AlH3 is ...
c. trigonal planar.
35. The 3-dimensional structure of NH3 is ...
d. trigonal pyramidal.
36. The 3-dimensional structure of CO2 is ...
a. linear.
37. The 3-dimensional structure of H2O is ...
b. bent.
38. The 3-dimensional structure of HI is ...
a. linear.
39. The 3-dimensional structure of BCl3 is ...
c. trigonal planar.
40.
The properties of metals are best described by the use of
____________ .
b. metal ions surrounded by a sea of electrons
41.
The electrical conductivity in metals (in their elemental
state) is best described using ____________.
a. a sea of electrons
19. The B—F bond in BF3 is ...
a. ionic.
20. In which of these compounds is the bond between the
atoms a nonpolar covalent bond?
d. Cl2
Honors Chemistry
Unit 4 Sample Problems (Key)
Page 2 of 5
42.
Which statement or statements are correct when barium
and oxygen react to form an ionic compound?
I. Barium atoms lose 2 electrons and form a cation.
II. Oxygen atoms form oxide anions (O2–).
III. In the compound, the ions are present in a one cation
to one anion ratio.
d. I, II, and III
44.
Which statement or statements are correct when
potassium and iodine react to form an ionic compound?
I. Potassium atoms lose 1 electron and form a cation.
II. Iodine atoms form iodide anions (I2–).
III. In the compound, the ions are present in a two cation
to one anion ratio.
a. I only
43.
Which statement or statements are correct when calcium
and chlorine react to form an ionic compound?
I. Chlorine atoms gain 1 electron and form an anion.
II. Calcium atoms lose 2 electrons and form a cation.
III. In the compound, the ions are present in a one cation
to one anion ratio.
a. I and II only
45.
Which statement or statements are correct when
aluminum and oxygen react to form an ionic compound?
I. Aluminum atoms lose 3 electrons and form a cation.
II. Oxygen atoms form oxide anions (O2–).
III. In the compound, the ions are present in a three cation
to two anion ratio.
a. I and II only
46.
Fully describe the feature or features of metallic bonding that explains the electrical conductivity of metals in their normal state.
The principle feature of metallic bonding is the lattice structure of metal ions surrounded by a sea of electrons. These
delocalized electrons are free to move throughout the metal. Therefore, when an electron is put into one side of the
metal, it easily pushes another electron out the other side.
47.
Fully describe the feature or features of ionic bonding that explains the electrical conductivity of ionic compounds in aqueous
solution.
When ions are dissolved in water, they are dissociated into positive and negative ions in solution. These ions move easily
through the water. When a voltage is set up in the solution, the positive charges move toward the negative pole and the
negative charges move toward the positive pole. This is the movement of charge which is conductivity.
48.
Fully describe the feature or features of ionic bonding that explains the electrical nonconductivity of ionic compounds in the
solid state.
The cations and anions in a solid crystalline lattice are firmly held in place by the charges surrounding them. Therefore,
the ions do not move even when a large voltage is placed across the crystal. This results in the crystal being
nonconductive.
49.
Distinguish between the structure of a metallic bond, the structure of an ionic compound, and the structure of an extended
covalent network.
The metallic bond involves a lattice structure of metal cations surrounded by a sea of electrons. The structure of an
ionic compound is composed of a lattice of cations and anions arranged to give a neutral overall charge. The structure of
an extended covalent network involves atoms sharing pairs of electrons over a very large scale in a continuous network.
50.
Determine the formula for each of the following binary ionic compounds.
a. iron(II) iodide
FeI2
c. chromium(III) fluoride
CrF3
e. manganese(II) nitride
Mn3N2
g. cobalt(II) chloride
CoCl2
i. gold(III) phosphide
AuP
k. tin(II) fluoride
SnF2
b. calcium sulfide
CaS
d. potassium nitride
K3N
f. gallium oxide
Ga2O3
h. mercury(II) iodide
HgI2
j. lead(IV) sulfide
PbS2
l. gold(I) chloride
AuCl
Honors Chemistry
m. titanium(III) oxide
Ti2O3
o. titanium(IV) fluoride
TiF4
51.
sodium iodide
c. TiO
titanium(II) oxide
e. CuO
copper(II) oxide
g. ZnS
zinc sulfide
i. CuCl
copper(I) chloride
k. Fe2S3
iron(III) sulfide
m. TiO2
titanium(IV) oxide
o. HgO
mercury(II) oxide
TiO
p. manganese(III) fluoride
MnF3
b. Mn3P2
manganese(II) phosphide
d. Na2O
sodium oxide
f. AlCl3
aluminum chloride
h. AgCl
silver chloride
j. SnCl2
tin(II) chlroide
l. Hg2I2
mercury(I) iodide
n. V3N2
vanadium(II) nitride
p. Mn3N4
manganese(IV) nitride
Determine the formula for each of the following polyatomic ionic compounds.
a. sodium nitrate
NaNO3
c. aluminum phosphate
AlPO4
e. magnesium nitrite
Mg(NO2)2
g. copper(II) carbonate
CuCO3
i. gold(III) chromate
Au2(CrO4)3
k. tin(IV) sulfite
Sn(SO4)2
m. titanium(II) dichromate
TiCr2O7
o. ammonium nitrate
NH4NO3
53.
n. titanium(II) oxide
Determine the name for each of the following binary ionic compounds.
a. NaI
52.
Unit 4 Sample Problems (Key)
b. calcium sulfate
CaSO4
d. potassium hydroxide
KOH
f. gallium perchlorate
Ga(ClO4)3
h. silver chlorate
AgClO3
j. lead(II) chlorite
Pb(ClO3)2
l. copper(I) hypochlorite
CuClO
n. titanium(III) phosphate
TiPO4
p. manganese(III) hydrogen carbonate
Mn(HCO3)3
Determine the name for each of the following polyatomic ionic compounds.
a. KClO
potassium hypochlorate
b. Mg3(PO4)2
magnesium phosphate
Page 3 of 5
Honors Chemistry
Unit 4 Sample Problems (Key)
c. Al(ClO4)3
d. (NH4)2SO3
aluminum perchlorate
ammonium sulfite
e. CaO2
f. Ga(NO2)3
calcium peroxide
gallium nitrite
g. ZnCO3
h. AgClO2
zinc carbonate
silver chlorite
i. CuO2
j. Sn(ClO4)4
copper(II) peroxide
tin(IV) perchlorate
k. Fe2(SO4)3
l. HgCrO4
iron(III) sulfate
mercury(II) chromate
m. TiCr2O7
n. V(NO3)2
titanium(II) dichromate
vanadium(II) nitrate
o. Hg3(PO4)2
p. Mn(HCO3)4
mercury(II) phosphate
54.
Page 4 of 5
manganese(IV) hydrogen carbonate
Draw the Lewis structure for each of the following covalent compounds. Include all lone pairs.
a. H2O
..
H – .O. – H
b. NH3
..
H–N–H
H
c. CH4
H
H–C–H
H
d. BF3
..
..
:F
.
. . – B – .F:
:F:
..
e. CO2
f. HCN
..
..
..
.O. = C = O
H–C–N
g. I2
h. HNO (N is the central atom)
i. PF3
.. ..
:I.. – ..I:
j. CH2O
..
H – C = .O.
.. ..
H – N = .O.
k. C2H2
l. C2H4
H–C–C–H
H–C=C–H
H
H
55.
.. .. ..
:F
. . – P – .F:.
:F:
..
H
Determine the 3D structure around the central atom for each of the following covalent compounds.
a. H2O
bent
d. BF3
trigonal planar
g. I2
b. NH3
trigonal pyramid
e. CO2
linear
h. HNO (N is the central atom)
linear
bent
j. CH2O
k. C2H2
trigonal planar
linear
c. CH4
tetrahedral
f. HCN
linear
i. PF3
trigonal pyramid
l. C2H4
trigonal planar
Honors Chemistry
56.
Unit 4 Sample Problems (Key)
Page 5 of 5
Draw the direction of polarization for each of the following bonds. An example of showing the direction of polarization in the
H-O bond would be σ+ HO σ-.
a. S – O
b. C – H
σ+
σ
S  O σ
d. H – F
σ+
HF
c. O – Cl
C  H σ+
e. I – Br
σ
σ+
I  Br
σ
O  Cl σ+
f. C – N
σ
σ+
C  N σ