Chemistry 11 Fall 2011
Examination #1 ANSWER KEY
For the first portion of this exam, select the best answer choice for the questions below and mark
the answers on your scantron. Pay attention to significant figures. Then answer the free
response questions that follow (100 pts. total; multiple choice 2 pts. each).
1.
Determine the expected electronic configuration for Ac+3 (Z = 89)
A.
B.
C.
D.
E.
2.
List the following in order of increasing ionization energy: Ca, N, Cs, F, and K.
A.
B.
C.
D.
E.
3.
F < N < Ca < K < Cs
N < F < K < Ca < Cs
Cs < K < Ca < N < F
Cs < Ca < K < F < N
K < Cs < Ca < N < F
How many protons, neutrons, and electrons present in 186 W3+?
A.
B.
C.
D.
E.
5.
F < N < Ca < K < Cs
N < F < K < Ca < Cs
Cs < K < Ca < N < F
Cs < Ca < K < F < N
K < Cs < Ca < N < F
Now rank the species in #2 above in order of increasing electronegativity.
A.
B.
C.
D.
E.
4.
1s2 2s2 2p6 3s2 3p6 4s2 4d10 4p6 5s2 5d10 5p6 6s2 6f14 6d10 6p4
1s 2 2s 2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s1
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p5
1s2 2s2 2p6 3s2 3p6 4s2 4d10 4p6 5s2 5d10 5p6 6s2 6f14 6d10 6p6
183 protons; 186 neutrons; 74 electrons
183 protons; 74 neutrons; 186 electrons
186 protons; 74 neutrons; 183 electrons
74 protons; 112 neutron; 77 electrons
74 protons; 112 neutrons; 71 electrons
What is the name of the following compound: Cu2 S?
A.
B.
C.
D.
E.
copper sulfide
copper(I) sulfide
copper(II) sulfide
copper(IV) sulfide
dicopper monosulfide
6.
The density of acetic acid is 1.05 g/mL. How many mL are contained in 327 g of acetic
acid?
A.
B.
C.
D.
E.
7.
The temperature required to melt NaCl is 528 C. What is this temperature converted to
Fahrenheit and Kelvin?
A.
B.
C.
D.
E.
8.
2.91 x 10-3 mL
3.21 x 10-3 mL
2.62 x 102 mL
3.11 x 102 mL
3.43 x 102 mL
-44 F and 231 K
-0 F and 255 K
491 F and 528 K
982 F and 801 K
1299 F and 977 K
Two electronic balances are tested using a standard weight. The true mass of the
standard is 1.3111 g. The results of 5 individual measurements on each balance are
recorded below:
Balance A: 0.8888 g, 0.9959 g, 1.1182 g, 1.0033 g, and 0.9938 g; avera ge = 1.0000 g
Balance B: 1.3110 g, 1.3109 g, 1.3111 g, 1.3110 g, and 1.3110 g; average = 1.3110 g
Which statement best describes the results?
A.
B.
C.
D.
E.
9.
A: good precision, good accuracy. B: good precision, good accuracy.
A: good precision, good accuracy. B: poor precision, poor accuracy.
A: poor precision, good accuracy. B: good precision, good accuracy.
A: poor precision, poor accuracy. B: good precision, good accuracy.
A: poor precision, poor accuracy. B: good precision, poor accuracy.
Which of the following is/are chemical properties of iodine?
I.
II.
III.
A.
B.
C.
D.
E.
Iodine is a purple solid at 25 C.
Iodine reacts with sodium metal to form sodium iodide.
The density of iodine is 4.93 g/cm3 .
I only
II only
III only
I and II
I and III
For Questions 10 - 13, consider the structure of Fluoxetine (or Prozac) below, a drug approved
for the treatment of major depression, obsessive-compulsive disorder, bulimia nervosa, panic
disorder, and premenstrual dysphoric disorder:
H
H
C
HC
C
CH
CH
F3C
H2
C
O
C
H
N
C
H2
CH3
C
HC
CH
HC
CH
C
H
Fluoxetine (Prozac)
10.
Select “A” for True OR “B” for False regarding the following statement: Fluoxetine
possesses resonance.
11.
Select “A” for True OR “B” for False regarding the following statement: Fluoxetine is
considered an overall nonpolar molecule.
12.
What is the molecular geometry around the oxygen atom?
A.
B.
C.
D.
E.
13.
linear
trigonal planar
bent
trigonal pyramidal
tetrahedral
Determine the approximate bond angle around the H-N-C bond?
A.
B.
C.
D.
E.
90
109.5
120
180
Cannot be approximated
14.
If the fuel efficiency of an automobile is 27 miles per gallon, what is its fuel efficiency in
kilometers per liter? (1 km = 0.621 mile, 1.000 L = 1.057 quarts, 4 quarts = 1 gallon)
A.
B.
C.
D.
E.
15.
Which of the species below has the smallest radii?
A.
B.
C.
D.
E.
16.
9.1 C
22.0 C
34.9 C
47.0 C
616 C
How many lone pair set of electrons, if any, surround the central atom in SO 2 ?
(Lone pairs on terminal oxygen atoms omitted for clarity)
A.
B.
C.
D.
E.
18.
Mg
Mg+
Mg2+
MgMg2-
If 46.0 g of ethanol, CH3 CH2 OH, at 22.0 C absorbs 1.45 kJ of heat, what is the final
temperature of the ethanol? The specific heat of ethanol is 2.44 J/g C.
A.
B.
C.
D.
E.
17.
11 km/L
14 km/L
17 km/L
63 km/L
180 km/L
0
1
2
3
4
S
O
S
O
O
O
Which statement concerning solid NaCl (i.e., table salt) is expected to be TRUE?
A.
B.
C.
D.
E.
NaCl is a che mical compound.
NaCl is a homogeneous mixture.
NaCl is a heterogeneous mixture.
NaCl has properties identical to its component elements, sodium metal and
chorine gas.
Both A and B
19.
Determine the correct answer to the following expression: 2.97 x 10 -5 + 6.13 x 10-3
A.
B.
C.
D.
E.
6.1 x 10-3
6.16 x 10-3
6.160 x 10-3
6.1597 x 10-3
6.15970 x 10-3
For Questions 20 - 25, match the vocabulary terms to their respective definitions/descriptions.
A.
B.
C.
D.
E.
AB.
sublimation
deposition (#23)
condensation
pure substance
element (#22)
mass number (#24)
BC.
CD.
DE.
ABC.
BCD.
CDE.
atomic number (#25)
atomic mass
heat (#21)
metal
nonmetal
metalloid (#20)
20.
malleable, ductile, oxidizes, poor conductor of heat and electricity, and low melting point
21.
energy that flows into or out of a system because of a difference in temperature between
the system and its surrounding
22.
a specific substance which cannot be decomposed into simpler substances by ordinary
chemical means
23.
conversion of matter from a gas into a solid with bypassing the liquid phase
24.
the number of protons and neutrons in the nucleus of an atom
25.
the number of protons in the nucleus of an atom
26.
(6 pts.) Your physician orders 125 mg of medication per hour. The label on the IV bag
reads 5 g/1000 mL. The set delivers 15 gtts/mL, where the unit "gtts" stands for drops of
liquid. How many mL should infuse each hour? The current flow rate is 10 gtts/min. Is
this correct? If not, what is the correct flow rate?
?
=
x
x
= 25 mL/hr
Use the current flow rate provided in the proble m, 10 gtts/min, to determine if equal
to 25 mL/hr:
?
=
x
x
= 40 mL/hr; since this is NOT equal to 25
mL/hr, work backwards to determine what the flow rate should be:
=
x
x
; X = 6.25 gtts/min (or 6 gtts/min in a clinical
setting)
27.
(16 pts. total; 2 pts. each) Write the name/chemical formula for each of the
following listed below:
A.
chromium(III) sulfite
Cr2 (SO3 )3
B.
aluminum phosphate
AlPO4
C.
PF5
phosphorus tetrafluoride
D.
Ag2 CO3
silver carbonate
E.
strontium hydroxide
Sr(OH)2
F.
ammonium acetate
NH4 C2 H3 O2
G.
zinc nitrate
Zn(NO3 )2
H.
N2O
dinitrogen monoxide
(Exam Continued on Next Page)
28.
(28 pts. total) Consider each of the following ions/molecules shown below and write your
final structures in the boxes provided:
A.
B.
C.
D.
Beginning with the best Lewis dot structure, use VSEPR theory to draw each of
the listed species, including resonance where appropriate. Don’t forget to include
lone pairs!
Describe the geometry about EACH central atom. Include both electronic and
molecular geometries.
Give the approximate bond angle(s) around each central atom.
Determine whether the overall species is ionic, polar, and/or nonpolar.
H
C2
H
H
C
H
N
O
C
H
C1 O
Structure #1
electronic geometries: (N) tetrahedral; (C1) tetrahedral
(C2) trigonal planar; (O) tetrahedral
molecular geometries: (N) trigonal pyramidal; (C1) tetrahedral;
(C2) trigonal planar; (O) bent
approx. bond angles: (N) 109.5; (C1) 109.5; (C2) 120;
(O) 109.5
polar or nonpolar? polar
O
Cl
O
O
O
Structure #2
O
C
H
C
O
H
O
Structure #3
electronic geometry: tetrahedral
electronic geometry: trigonal planar
molecular geometry: trigonal pyramidal
molecular geometry: trigonal planar
approx. bond angle: 109.5
approx. bond angle: 120
polar or nonpolar? ionic; polar
polar or nonpolar? ionic; polar