Name: ________________________
Problem Set - Structures and Properties Unit v. 0217
Knowledge
Inquiry
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Communication
/35
Application
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Knowledge (25 marks)
1. Which of the following did the Bohr model of the atom help explain?
a. Nuclear structure
d. Atomic spectra
b. Structure of the electron
e. Structure of the alpha particle
c. Wave property of the atom
2. Which of the following is an example of a covalent network solid?
a. Sodium, Na(s)
c. Graphite, C(s)
b. Sucrose, C12H22O11
d. Magnesium fluoride, MgF2(s)
3. Which of the following electron configurations is impossible for an atom, regardless of whether it is
in the ground state or an excited state?
a. 1s22s22p3
d. 1s32s12p4
b. 1s22s12p1
e. 1s22s12p3
c. 1s22s22p6
4. Which of the following molecules does NOT have a linear shape?
a. HCl
d. OCS
b. CO2
e. BeF2
c. XeF2
5. Which of the following electron configurations shows a transition metal atom?
a. 1S22s22p5
d. 1s22s22p63s23p63d104s24p3
b. 1s22s22p63s23p1
e. 1s22s22p63s23p63d34s2
c. 1s22s22p63s23p63d104s24p1
6. A substance has a melting point of 1850OC and a boiling point of 2700OC is insoluble in water and is
a good insulator of electricity. The substance is most likely
a. An ionic solid
d. A covalent network solid
b. A polar covalent solid
e. A nonpolar covalent solid
c. A metallic crystal
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7. These are the known spectra for four common gases
followed by the spectrum recorded by a telescope for
a distant star.
What gases are present in the distant star?
____________________________________
Distant
Star
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8. a) Draw the full electron configuration for Krypton.
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b) Give an anion and a cation that are isoelectronic with Krypton.
Anion _________________
Cation __________________
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9. For each type of solid, place the appropriate letter (corresponding to the descriptions below) in the each
of the boxes (each number may only be used once). [8 x ½ = 4]
Type of Solid
Observations
Example
Ionic Crystal
Metallic Crystal
Molecular Crystal
Covalent Network Crystal
a. Extremely strong and hard, non-conductors of electricity
b. Low melting point, non-conductors of electricity
c. Good conductor of electricity, shiny
d. High melting point, conducts electricity in the liquid not solid state
e. Diamond
f. Ice
g. Salt
h. Copper penny
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10. Identify the element that:
a. Contains a full 3rd energy level
_______
b. Contains 3 electrons in the 2p level
__
c. Outer energy level is 4s2
d. Contains 5 electrons in the 4d level ________
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11. Explain why the boiling point of methylamine CH3NH2 is -6C, while that of ethane C2H6 is -89C.
/2
12. Name the forces acting between particles in each of the following substances:
a) Hexane, C6H14 (l) _________________
b) 1 butanol, C4H9OH(l) ______________
c) Calcium carbonate CaCO3 (s) ________________
d) Diamond Cn (s) ______________________
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Inquiry (35 marks)
1. Fill in the following table comparing these 2 compounds: (6 marks)
Compound
3D Lewis
Structure
with dipoles
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Hybrid
ization
Shape name
/1
/1
Polar
bonds?
Yes/No
/1
Polar
molecule?
Yes/No
/1
Major
intermolecular
Force
/1
SF4
XeF2
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2. The charge on an ion of nickel can be either +2 or +3
Draw the energy level diagram for the neutral atom and for each ion. (3 marks)
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3. For Titanium
a. Write the short form electron configuration (2 marks)
/2
Water
soluble?
Yes/No
/1
b. Give the 4 quantum numbers for the last electron in titanium.
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c. Is titanium paramagnetic or diamagnetic? Explain
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4. Which of the pure substances has the stronger intermolecular force compared to the other? Explain.
beryllium difluoride, BeF2 or oxygen difluoride, OF2
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5.
a) Draw the Lewis Structure for CS2.
/1
b) Class: __________________
VSEPR shape: _________________________
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c) Show the energy level diagrams and indicate hybridization for all of the atoms in CS2.
/2
d) Draw the valence bond theory diagram for CS2. Label all  and  bonds.
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Communication (15 marks)
1. a) BCl3 and NF3 both have 3 atoms around their central atom. However, according to VSEPR
theory they have different shapes. Explain why. (2 marks)
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b) Explain which intermolecular forces will act on these molecules, and why.
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e) Compare melting and boiling points of these molecules based on their structures.
/2
2. Draw Lewis Structures for each of the following and identify the VSEPR shape and hybridization. Show
any resonance structures if applicable. (3 marks each)
a. Cl031-
b. SO2
c. PF5
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Application (25 marks)
1. a) What two elements in period 4 are exceptions to the way we normally write electron
configurations?
/2
b) Write the predicted and the actual configuration of each.
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c) What rules for drawing energy level diagrams are followed for the above elements? What rules
are violated?
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2. The following graph shows the general trend in ionization energy across the periods of the periodic
table.
Examine the trend in ionization energy for each period.
a. Which two groups are exceptions to the trend for ionization energy? ___________________ (hint:
the same groups will show exceptional behavior in all of the periods)
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b. Draw the energy level diagram for the first element in period 2 that does not follow the trend.
/2
c. Using the electron arrangement as evidence, explain why this element does not follow the trend.
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d. Draw the energy level diagram of the second element in period 2 that does not follow the trend.
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e. Using the electron arrangement as evidence, explain why this element does not follow the trend.
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6. Four hydrocarbons have their boiling points shown below. Hydrocarbons are nonpolar molecules.
Analyze the information in the table below to determine a pattern and explain the pattern using
knowledge of molecules and intermolecular forces. (2 marks)
Compound
Ethane
Propane
Butane
Pentane
Formula
C2H6
C3H8
C4H10
C5H12
Boiling point (C)
-89
-42
-0.5
36
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7. Use the energy level diagram provided below to answer the following:
Identify the element represented by this diagram.
_________________
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a) On the diagram, circle the electron that is most
likely described by the set of quantum numbers:
n = 4, l = 1, ml = -1, ms = - ½
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b) Show on the diagram, where the most likely
location would be to add an electron during the
formation of an anion and provide the quantum
numbers for the electron you added.
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c) Write the quantum numbers of the most likely
electron to be removed during the formation of a cation (1+)
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