Exam #1

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Chemistry 106: General Chemistry
Syracuse University
Exam #1, Fall 2003
Name
Date
The last page of this exam is a periodic table.
(1)
Platinum has a density of 21.4 g/cm3. What is the mass of 5.9 cm3 of this metal?
(express correctly the number of significant figures in your answer)
(a)
(b)
(c)
(d)
(e)
(2)
The number of significant figures in the mass measured as 0.05010 is
(a)
(b)
(c)
(d)
(e)
(3)
1
2
3
4
5
How many cubic centimeters equals one cubic meter?
(a)
(b)
(c)
(d)
(e)
(4)
0.276 g
1.3 x 102 g
126. g
3.6 g
3.63 g
109
106
103
10-6
10-9
The experiment performed in Rutherford's laboratory on the scattering of particles
by gold foil:
(a)
(b)
(c)
(d)
(e)
CHE 106
confirmed the plum-pudding model of the atom.
led to the discovery of the atomic nucleus.
utilized the deflection of beta particles by the gold foil.
determined he charge of an electron
involved none of the above
1
Fall 2002 Exam Questions
(5)
Which of the following statements is/are incorrect?
I.
II.
III.
IV.
(a)
(b)
(c)
(d)
(e)
(6)
protons
electrons
neutrons
isotopes
nucleons
What is the mass in grams of 4.25 x 1022 molecules of water?
(a)
(b)
(c)
(d)
(e)
(8)
III
III and IV
I, II, and III
II, III, and IV
I and II
The following species, 34Se2-, 36Kr, and 38Sr2+, all have the same number of
(a)
(b)
(c)
(d)
(e)
(7)
The formula for calcium phosphate is Ca2(PO4)3.
The formula for iron(III) sulfide is FeS.
The correct name for Mg(CO3)2 is manganese carbonate.
The formula for gallium nitride is GaN.
0.0127 g
1.27 g
1.42 g
14.2 g
7.65 x 1023 g
You are a space explorer who has traveled to a special planet in a far-off galaxy.
This planet is identical to Earth in size and chemical composition. You find a
chemistry textbook (always the first thing you should look for when away from
home) and learn that on that planet the mass of as 12C6 atom is defined as 12 amu
but the formal definition of a mole is the "quantity of any substance that contains
as many atoms, molecules, or formula units as the number of atoms in exactly 6
grams of 12C6". What then would be the molar mass of methane (CH4) as shown in
this textbook?
(a)
(b)
(c)
(d)
(e)
CHE 106
32.0 g
16.0 g
8.0 g
6.0 g
cannot be determined from the information given.
2
Fall 2002 Exam Questions
(9)
Which of the following statements is/are correct?
I.
II.
The molecular weight of sodium sulfide is 55.1 amu.
In a mole of CuSO4.5H2O there are 9 times Avogadro's number of oxygen
atoms.
III. A compound whose empirical formula is CH2O and molecular weight is
180.0 amu has a molecular formula of C4H8O2.
IV. Starting with 20 moles of H2, one can produce 30 moles of NH3 using the
Haber Process: N2(g) + 3 H2(g) ------> 2 NH3.
(a)
(b)
(c)
(d)
(e)
(10)
The formula of the carbonate ion, ammonium ion, and the chlorate ion are
represented, respectively, as
(a)
(b)
(c)
(d)
(e)
(11)
CO32-, NH21-, ClO31CO32-, NH3+, ClO21CO21-, NH4+, ClO1CO32-, NH4+, ClO31P3-, NH3+, ClO21-
The formula for aluminum sulfate is
(a)
(b)
(c)
(d)
(e)
(12)
I and II
II and III
III and IV
II
I and IV
Al2(CO3)3
Al2(SO4)3
Al3(SO4)2
Al2S3
Al3S2
The complete combustion of octane, C8H18, yields carbon dioxide and water:
C8H18 +
O2 ------>
CO2 +
H2O
The coefficient of oxygen in the balanced equation is
(a)
(b)
(c)
(d)
(e)
CHE 106
17
19
23
25
34
3
Fall 2002 Exam Questions
(13)
Which one of the following equations is properly balanced?
(a)
(b)
(c)
(d)
(e)
(14)
How many atoms of carbon are there in 0.40 mole of procaine, C13H20N2O2, a
"pain killer" used by dentists?
(a)
(b)
(c)
(d)
(e)
(15)
4.8 x 1023
9.6 x 1023
3.1 x 1023
6.3 x 1024
9.6 x 1024
What is the mass of oxygen in 0.375 mol of Co(CO)8?
(a)
(b)
(c)
(d)
(e)
(16)
NH4NO3 ------> 2 H2O + N2
CH3CHO + 3 O2 ------> 2 CO2 + 2 H2O
Sn + 4 HNO3 ------> SnO2 + 4 NO2 + 2 H2O
2 Na2SO4 + 3 Bi(NO3)3 ------> Bi2(SO4)3 + 9 NaNO3
Na2CO3 + 2 H2SO4 ------> Na2SO4 + 2 H2O + CO2
16.0 g
32.0 g
48.0 g
64.0 g
80.0 g
Elemental sulfur can be converted into sulfur trioxide by reaction with oxygen in
the presence of a catalyst. Upon addition of water, sulfuric acid is produced as
represented by the equation:
S8(s) + 12 O2(g) + 8 H2O(l) ------> 8 H2SO4(l)
What is the minimum mass of sulfur that is needed to prepare 175 g of H2SO4?
(a)
(b)
(c)
(d)
(e)
CHE 106
39.6 g
57.2 g
71.8 g
75.3 g
81.9 g
4
Fall 2002 Exam Questions
(17)
Which of the following statements is/are incorrect?
I.
II.
III.
(a)
(b)
(c)
(d)
(e)
(18)
H+(aq) + OH-(aq) ------> H2O(l) is the net ionic equation for the
neutralization of HNO3(aq) with KOH(aq).
HIO is a strong acid.
The net ionic equation for the reaction of Na2S with HBr is
S2-(aq) + 2H+(aq) ------> H2S(g).
I
II
III
I and II
II and III
Which of the following statements is/are incorrect?
I.
The spectator ions when lead(II) acetate(aq) is added to potassium
sulfate(aq) are C2H3O2-(aq) and K+(aq).
II. The net ionic equation when (NH4)2SO4(aq) is added to LiBr(aq) is:
Li+(aq) + SO42-(aq) ------> Li2SO4(s)
III. The molecular equation when NiCl2(aq) is added to Na3PO4(aq) is:
NiCl2(aq) + Na3PO4 ------> NR
(a)
(b)
(c)
(d)
(e)
(19)
I
II
I and II
I and III
II and III
What is the volume (mL) of a 0.225 M NaOH solution needed to just neutralize
50.0 mL of a 0.0875 M H2SO4 solution, according to the reaction:
2 NaOH(aq) + H2SO4(aq) ------> 2H2O(l) + Na2SO4(aq)
(a)
(b)
(c)
(d)
(e)
CHE 106
19.0 mL
38.0 mL
57.1 mL
76.1 mL
None of the above.
5
Fall 2002 Exam Questions
(20)
In a laboratory, 35.0 mL of 6.0 M sulfuric acid was spilled. Before the spill could
be cleaned up, it had to first be neutralized with NaHCO3 according to the
equation:
H2SO4 + 2 NaHCO3 ------> 2 H2O + 2 CO2 + Na2SO4
The weight of NaHCO3 needed for neutralization of the spill was
(a)
(b)
(c)
(d)
(e)
(21)
If 25.8 mL of a AgNO3 solution is needed to precipitate all of the chloride in 895
mg of KCl (forming AgCl), the molarity of the AgNO3 solution is
(a)
(b)
(c)
(d)
(e)
(22)
12.0 M
0.347 M
0.465 M
0.0847 M
0.012 M
Aqueous solutions of sodium sulfide and copper(II) chloride are mixed together.
Which statement if correct?
(a)
(b)
(c)
(d)
(e)
(23)
0.42 g
8.8 g
18 g
21 g
35 g
Both NaCl and CuS precipitate from the solution.
No precipitate forms.
CuS will precipitate from solution.
NaCl will precipitate from solution.
No reaction will occur.
A 230 mL sample of a 0.275 M solution is left on a hotplate overnight. The
following morning the solution is 1.1 M. What volume of solvent has evaporated
from the 0.275 M solution?
(a)
(b)
(c)
(d)
(e)
CHE 106
58 mL
63.3 mL
172 mL
230 mL
288 mL
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Fall 2002 Exam Questions
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