Chemistry 122
Exam 1
Spring 2008
April 24, 2008
Oregon State University
Dr. Richard Nafshun
Instructions: You should have with you several number two pencils, an eraser, your 3" x 5" note card, a
calculator, and your University ID Card. If you have notes with you, place them in a sealed backpack
and place the backpack OUT OF SIGHT or place the notes directly on the table at the front of the room.
Fill in the front page of the Scantron answer sheet with your last name, first name, middle initial, and
student identification number. Leave the class section number and the test form number blank.
This exam consists of 25 multiple-choice questions. Each question has four points associated with it.
Select the best multiple-choice answer by filling in the corresponding circle on the rear page of the
answer sheet. If you have any questions before the exam, please ask. If you have any questions during
the exam, please ask the proctor. Open and start this exam when instructed. When finished, place your
Scantron form in the appropriate stack and present your University ID Card to the proctor. You may
keep the exam packet, so please show your work and mark the answers you selected on it.
Please read each exam question carefully. Terms such as correct, false, unpaired, pairs, H-C-F bond angle, H-C-H
angle, greatest, and smallest are used.
1.
There are ___ unpaired electrons in a ground-state oxygen atom.
(A)
(B)
(C)
(D)
(E)
2.
There are ___ unpaired electrons in a ground-state magnesium ion (Mg2+).
(A)
(B)
(C)
(D)
(E)
3.
0
1
2
3
4
The ground-state electron configuration of a nitrogen atom is:
(A)
(B)
(C)
(D)
(E)
4.
0
1
2
3
4
1s22s23s23p1
1s22s23s1
1s22s22p5
1s22s22p3
1s22s23s3
The ground-state electron configuration of a sodium ion (Na+) is:
(A)
(B)
(C)
(D)
(E)
1s22s23s23p2
1s22s23s1
1s22s22p6
1s22s22p63s23p2
1s22s22p4
5.
Consider Ba, F, Ge, O, and Al. The atom with the largest atomic size is:
(A)
(B)
(C)
(D)
(E)
6.
Consider Li, Li+, F, and F-. Which of the following statements is correct?
(A)
(B)
7.
Li is larger than Li+
F is larger than F-
A ground-state carbon atom has:
(A)
(B)
(C)
(D)
(E)
8.
Ba
F
Ge
O
Al
0 valence electrons.
2 valence electrons.
4 valence electrons.
6 valence electrons.
8 valence electrons.
Consider an oxygen atom in the ground-state. Which of the following statements is false?
(A)
(B)
(C)
(D)
(E)
An oxygen atom has 8 total electrons; 2 are core electrons and 6 are valence electrons.
The Lewis Dot Structure for an oxygen atom has 6 electrons (dots).
An oxygen atom is larger than a nitrogen atom.
There are two unpaired electrons in the oxygen atom.
The oxygen atom is paramagnetic.
9.
The Lewis Dot Structure of ammonia, NH3, depicts:
(A)
(B)
(C)
(D)
(E)
10.
The nitrogen-oxygen bond order in the nitrate ion (NO3-) is:
(A)
(B)
(C)
(D)
(E)
11.
There are no lone pairs of electrons
There is one lone pair of electrons
There are two lone pairs of electrons
There are three lone pairs of electrons
There are four lone pairs of electrons
1.00
1.33
1.50
1.75
2.00
A student (
) proposes the Lewis Dot Structure below for ClO2-. Determine the formal
charges on each atom in this structure.
(A)
(B)
(C)
(D)
(E)
The left oxygen has a formal charge of 0; the chlorine -1; and the right oxygen 0
The left oxygen has a formal charge of -1; the chlorine -1; and the right oxygen 0
The left oxygen has a formal charge of 0; the chlorine -1; and the right oxygen -1
The left oxygen has a formal charge of 0; the chlorine 0; and the right oxygen -1
The left oxygen has a formal charge of -1; the chlorine 0; and the right oxygen 0
12.
The H-O-H bond angle in water, H2O, is:
(A)
(B)
(C)
(D)
(E)
13.
Tetrafluoromethane, also known as carbon tetrafluoride, Freon-14 and R 14, is CF4. The
molecular geometry of CF4, is:
(A)
(B)
(C)
(D)
(E)
14.
bent
trigonal planar
trigonal pyramidal
tetrahedral
octahedral
The molecular geometry of SF6 is:
(A)
(B)
(C)
(D)
(E)
15.
180
120
109.5
A little greater than 109.5
A little less than 109.5
bent
trigonal planar
trigonal pyramidal
linear
octahedral
Consider O, P, Al, Zn, and Fr. The atom with the greatest electronegativity is:
(A)
(B)
(C)
(D)
(E)
O
P
Al
Zn
Fr
16.
The H-C-H bond angle in monofluoromethane (CH3F) is:
(A)
(B)
(C)
(D)
(E)
17.
Consider H2O, CH3F, NH3, CO2, and NO. Which is a non-polar molecule?
(A)
(B)
(C)
(D)
(E)
18.
H2O
CH3F
NH3
CO2
NO
Draw the structure of ethene, C2H2. Ethene contains:
(A)
(B)
(C)
(D)
(E)
19.
90
120
109.5
A little greater than 109.5
A little less than 109.5
no -bonds
one -bond
two -bonds
three -bonds
four -bonds
There are ________ resonance forms for ozone, O3.
(A)
(B)
(C)
(D)
(E)
0
1
2
3
4
20.
Consider the molecule below and identify the correct statement.
(A)
(B)
(C)
(D)
(E)
21.
Consider C2H6, C2H4, and C2H2. Which of these has the strongest carbon-carbon bond?
(A)
(B)
(C)
22.
There is one carbon that has an sp3 hybridization scheme.
There are two carbons that have sp3 hybridization schemes.
There are three carbons that have sp3 hybridization schemes.
There are four carbons that have sp3 hybridization schemes.
There are five carbons that have sp3 hybridization schemes.
C2H6
C2H4
C2H2
Consider MO (Molecular Orbital Theory). For the N2 molecule, there are ___________
electrons in the π2p* anti-bonding orbitals?
(A)
(B)
(C)
(D)
(E)
0
1
2
3
4
23.
Consider MO (Molecular Orbital Theory). The O2 molecule is:
(A)
(B)
(C)
(D)
(E)
24.
Molecular orbital theory predicts the F22+ ion (a positive two charge) has a bond order of:
(A)
(B)
(C)
(D)
(E)
25.
paramagnetic
diamagnetic
tetramagnetic
karaoke-magnetic
vegas-magnetic
0.0
1.0
1.5
2.0
3.0
Because of Chemistry 122...
(A)
(B)
(C)
(D)
(E)
I puke when I hear the name "Lewis."
I get lots of dates by using pick-up lines that include the words polar, paramagnetic,
electronegative, dipole, lobes, 180 degrees, see-saw, tetrahedral, and orbitals.
My taste in movies has improved.
I have laughed more times in the past four weeks than I have in the previous four years.
I am changing my major to chemistry... today!
[Any response will receive full credit; even no response.]