CH 221 FALL 2010 –MIDTERM 1
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CH 221 FALL 2010 - FIRST MIDTERM EXAM
Version 1
This exam has 22 questions worth 5 pts each, plus one question worth 2 pts.
The total possible score is 112 pts.
DO NOT OPEN THIS EXAM UNTIL TOLD TO DO SO
Before the exam begins you can do the following on the Scantron answer sheet. Use a #2
pencil.
1.
Fill in your name (LAST NAME, FIRST NAME) in the large box on the left. Don't
forget to bubble in the circles below your name.
2.
Fill in your student ID number in the box labeled "IDENTIFICATION NUMBER".
Do not use dashes or blank spaces. Fill in the circles as well.
3.
In the box labelled "CLASS SECTION NUMBER", enter the appropriate number
8 am class = section 001
9 am class = section 002
10 am class = section 003
11am class = section 004
12pm class = section 005
4.
In the lower right corner, in the box labelled "FORM NUMBER", write in the exam
version number (1, 2, 3, 4 etc.) given above in the shaded box and fill in the bubble.
ONLY ONE APPROVED NOTECARD IS ALLOWED
ALL PHONES AND OTHER ELECTRONIC DEVICES
OTHER THAN CALCULATORS MUST BE OFF
You may keep this exam packet and your notecard when the exam period is
complete.
Hand in the Scantron answer sheet to a TA at the end of the exam.
CH 221 FALL 2010 –MIDTERM 1
Periodic Table
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CH 221 FALL 2010 –MIDTERM 1
1.
Which of the following is a chemical property?
A.
B.
C.
D.
E.
The ductility (ease of deformation) of silver.
The ability of a hydrogen gas to fill a container of any size.
The ability of water to freeze, melt and boil.
The ability of oxygen to rust steel.
The ability of ZnO to produce a voltage if pressure is applied to it.
2.
Which of the following statements is NOT TRUE?
A.
B.
C.
D.
Gas molecules are far less densely packed than liquid molecules.
Solids are typically less densely packed than liquids
Evaporation is the phenomenon of a substance going from liquid to vapor.
Even though solids are typically tightly packed, it is still possible to chemically react
them.
Solid water is less dense than liquid water.
E.
3.
3
A.
B.
C.
D.
E.
Express the answer to the following to the correct number of significant figures:
(2.54 × 10-3 mol × 738.3254 g/mol) + 4.3 g
6.18 mol
6.176 g
6.2 g
6.18 g
6200 g
4.
Convert the volume of a cube with edges of 10.0 ft into liters. 1 in = 2.54 cm; 1 ft = 12 in
A.
B.
C.
D.
E.
0.305 L
305 L
1.64 x 104 L
2.83 x 104 L
2.83 x 107 L
CH 221 FALL 2010 –MIDTERM 1
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5.
In medicine it is common to have dosages listed in milligrams of drug per kilogram of
bodyweight (mg/kg). An oral dosage of 60.0 mg of codeine is common for a 180 lb man.
What is the dosage in mg/kg? [1.00 kg = 2.205 lbs]
A.
B.
C.
D.
E.
0.151 mg/kg
0.735 mg/kg
4.91 x 103 mg/kg
2.38 x 104 mg/kg
1.51 mg/kg
6.
Which of the following statements concerning early experiments and ideas about atomic
structure turned out to be TRUE?
A.
B.
C.
D.
E.
The atom consists of negative electrons floating in a background positive charge.
All carbon atoms are identical.
Most of the mass of an atom is concentrated in a small volume at the center.
The formation of a compound can result in the destruction of an atom.
Atoms consist solely of protons and electrons.
7. Which is the correct definition of mass number?
A.
B.
C.
D.
E.
The number of particles in the nucleus
The number of protons in the nucleus
The number of neutrons in the nucleus
The number of protons plus neutrons in the nucleus
The mass of a nucleus
8. Choose the correct symbol for the isotope of Fe that has 30 neutrons.
A.
B.
C.
D.
E.
30
26Fe
26
30Fe
52
26Fe
56
30Fe
56
26Fe
CH 221 FALL 2010 –MIDTERM 1
9.
Which of the following lists of elements is an element which tends to lose one electron
when forming an ionic compound, a noble gas, an element which tends to gain one
electron when forming an ionic compound, and a transition metal?
A.
B.
C.
D.
E.
F, Ne, Li, Fe
Na, Ne, Cl, Cr
Ba, Kr, Br, Cr
Cs, N, Ar, Fe
F, He, Rb, Al
10.
Chemium has two naturally occurring isotopes. 151Ch has a mass of 150.92 g/mol and is
18.82% abundant. 153Ch has a mass of 152.97 g/mol and is 81.18% abundant. What is
the average atomic mass of Chemium?
A.
B.
C.
D.
E.
151.31 g/mol
152.97 g/mol
150.92 g/mol
151.95 g/mol
152.58 g/mol
11.
Which of these statements is NOT CORRECT?
A.
B.
C.
D.
E.
Avogadro’s number is the number of H atoms in 1.0079 g of H atoms.
The mass of 2 moles of Fe atoms is twice the mass of 1 mole of Fe atoms.
1 mole of O2 contains 6.02 × 1023 O atoms.
If the atomic mass of an element is x amu, then its molar mass is x g/mol.
1 mole of H2O contains twice as many atoms of H as O.
12.
How many Ca atoms are there in 2.04 g of Ca? [NA = 6.022 x 1023]
A.
B
C.
D.
E.
4.92 × 1023 atoms
3.07 × 1022 atoms
4.92 × 1025 atoms
8.45 × 10-26 atoms
40.08 atoms
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CH 221 FALL 2010 –MIDTERM 1
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13.
Prazosin (trade names Minipress,Vasoflex,Pressin and Hypovase) is a sympatholytic drug
used to treat high blood pressure (hypertension). It belongs to the class of alphaadrenergic blockers, which lower blood pressure by relaxing blood vessels. There are
1.178 x 1024 Prazosin molecules in 750.0 g of Prazosin. What is the molar mass of
Prazosin?
A.
B.
C.
D.
E.
709.4 g/mol
318.7 g/mol
236.1 g/mol
383.4 g/mol
The answer cannot be calculated without the molecular formula of Prazosin.
14.
The molar mass of calcium acetate Ca(CH3COO)2 is:
A.
B.
C.
D.
E.
6.879 x 1025 g/mol
112.21 g/mol
158.17 g/mol
104.15 g/mol
99.13 g/mol
15.
Methyl salicylate (a compound that smells like wintergreen) contains:
A.
B.
C.
D.
E.
an alcohol functional group and a ketone functional group
an alcohol functional group and an ether functional group
an alcohol functional group and an ester functional group
an alcohol functional group and an amide functional group
an alcohol functional group and an aldehyde functional group
CH 221 FALL 2010 –MIDTERM 1
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16.
Upon combustion in excess oxygen, 0.4780 grams of a compound containing only
carbon, hydrogen, and oxygen produces 0.6780 grams of CO2 (g) and 0.4165 grams of
H2O (g). What is the empirical formula of the compound?
A.
B.
C.
D.
E.
C4H8O
C2H4O
CH2O
CH3O
C2H3O2
17.
What is the mass percent composition of sodium in sodium phosphate Na3PO4?
A.
B.
C.
D.
E.
42.1 %
20.0 %
34.7 %
11.1 %
14.0%
18.
When the reaction below is correctly balanced,
C11H24 (l)
+
O2 (g) →
CO2 (g) +
H2O (g)
A.
B.
C.
D.
E.
17 O2 are consumed
11 O2 are consumed
22 O2 are consumed
12 O2 are consumed
34 O2 are consumed
19 .
The name of Co3(PO4)2 is __________ and the name of N2O4 is ____________.
A.
B.
C.
D.
E.
cobalt(III) phosphate, dinitrogen tetroxide
cobalt(II) phosphate, dinitrogen tetroxide
cobalt(III) phosphate, nitrogen oxide
cobalt(II) phosphate, nitrogen oxide
tricobalt diphosphate, dinitrogen tetroxide
CH 221 FALL 2010 –MIDTERM 1
20.
Which of the following pairs of elements can combine to form an ionic compound?
A.
B.
C.
D.
E.
Sodium and calcium
Carbon and oxygen
Calcium and sulfur
Carbon and nitrogen
Fluorine and neon
21.
Aluminum metal dissolves in nitric acid to produce aluminum nitrate and hydrogen gas
as follows:
2Al (s) + 6HNO3 (aq) → 2Al(NO3)3 (aq) + 3H2 (g)
If 3.00 moles of aluminum metal are dissolved completely in an excess of nitric acid,
how many grams of hydrogen gas will be evolved by the reaction assuming a yield of
100%?
A.
B.
C.
D.
E.
4.03 g H2
4.54 g H2
9.07 g H2
2.02 g H2
6.05 g H2
22.
If 5.00 moles of iron metal are reacted with hydrochloric acid according to the following
reaction:
2Fe (s) + 6HCl (aq) → 2FeCl3 (aq) + 3H2 (g)
and the reaction yields 760 g of FeCl3, what is the percent yield of the reaction?
A.
B.
C.
D.
E.
55.5%
234%
46.9%
93.7%
97.2%
TWO POINT QUESTION
23.
Can you pass this class without passing the lab portion?
A.
Yes
B.
No
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