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Chemistry 106: General Chemistry
Syracuse University Project Advance
Exam #2, Fall 2001
Name
Date
The last page of the examination is a periodic table.
(1)
Which one of the following conditions would always result in an increase in E for a system?
(a)
(b)
(c)
(d)
(e)
(2)
The system loses heat and does work on the surroundings
The system gains heat and does work on the surroundings
The system loses heat and has work done on it by the surroundings
The system gains heat and has work done on it by the surroundings
Cannot predict what happens because w and q are not state functions
The value of H° for the following reaction is –126 kJ.
2 Na2O2(s) + 2 H2O(l) ------> 4 NaOH(s) + O2(g)
Determine the amount of heat (in kJ) that would be evolved by the reaction of 25.0 g of Na2O2
with water.
(a)
(b)
(c)
(d)
(e)
(3)
20.2
40.4
67.5
80.8
126
What is the resulting temperature when 35 g of water at 75° C is mixed with 15g of water at
15° C? (Heat capacity of water is 4.184 J/g °C)
(a)
(b)
(c)
(d)
(e)
CHE 106
33° C
48° C
57° C
75° C
120° C
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Fall 2001 Exam Questions
(4)
Given the following thermochemical equations:
Fe2O3(s) + 3 CO(g)
3 Fe(s) + 4 CO2(g)
H° = -28.0 kJ
H° = +12.5 kJ
2 Fe(s) + 3 CO2(g)
4 CO(g) + Fe3O4(s)
What is the value of H° for the reaction
3 Fe2O3(s) + CO(g)
(a)
(b)
(c)
(d)
(e)
(5)
CO2(g) + 2 Fe3O4(s)
kJ
kJ
 kJ
 kJ
-85 kJ
Use the information in the table to calculate H° (in kJ) for the following reaction
4 NH3(g) + 5 O2(g) ------> 4 NO(g) + 6 H2O(l)
Substance
H2O(l)
NO(g)
NO2(g)
HNO3
NH3(g)
(a)
(b)
(c)
(d)
(e)
(6)
Hf° (in kJ/mol)
-286
90
34
-207
-46
-1172
-150
-1540
-1892
none of the above
Use the information in the table to calculate H° (in kJ) for the following reaction
IF5(g) ------> IF3(g) + F2(g)
H° = ? kJ
IF(g) + F2(g) ------> IF3(g)
IF(g) + 2 F2(g) ------> IF5(g)
H° = -390 kJ
H° = -745 kJ
(a)
(b)
(c)
(d)
(e)
CHE 106
+355
-1135
+1135
+35
-35
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Fall 2001 Exam Questions
(7)
The heat capacity of copper metal is 0.38 J/g °C. Assume you had a 75 g cube of copper at
25° C. What would the final temperature of the copper be (in °C) if it absorbed 150 J of heat?
(a)
(b)
(c)
(d)
(e)
(8)
Each of the following statements describes the significance of a certain key experiment or
idea. Which one is not correct?
(a)
(b)
(c)
(d)
(e)
(9)
19.7
5.3
30.3
25.8
38.2
Planck’s successful explanation of the black-body radiation spectrum
introduced the hypothesis that radiation is emitted not continuously but in
discrete quanta.
Rutherford’s experiment on the scattering of alpha particles showed that the
mass of the nucleus is concentrated in a very small volume.
The electron diffraction experiment demonstrated Heisenberg’s hypothesis that
matter and energy are interconvertable.
The solution to the Schrodinger wave equation for the hydrogen atom does not
provide a detailed description of the electron’s position but only the probability
of finding the electron in a given region of space.
The phenomenon of radioactivity was discovered by Becquerel who observed
that uranium salts emitted radiation that penetrated the black paper covering of
photographic plates and darkened them as if they had been exposed to light.
Which sketch represents an orbital that can have a azmuthal quantum number of 2?
(1)
(a)
(b)
(c)
(d)
(e)
CHE 106
(2)
(3)
(4)
(5)
1
2 and 4
4 and 5
2 and 3
2, 3, 4 and 5
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Fall 2001 Exam Questions
(10)
Which of the following statements concerning the Bohr model of the hydrogen atom is not
true?
(a)
(b)
(c)
(d)
(e)
(11)
Which one of the following atoms has two unpaired electrons in the ground state?
(a)
(b)
(c)
(d)
(e)
(12)
The theory successfully explained the observed emission and absorption
spectra of the hydrogen atom.
The theory requires that the greater the energy of the electron in the hydrogen
atom, the greater its velocity.
The theory requires that the energy of an electron in the hydrogen atom have
only discrete values.
The theory requires that the radii of the circular orbits of the electron have only
discrete values.
The theory requires that an electron move only between two discrete orbits.
Na
Ca
P
O
Al
Which orbital diagram represents a violation of Pauli principle?
A
B
C
D
E
(a)
(b)
(c)
(d)
(e)
CHE 106
A
B
C
D
E
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Fall 2001 Exam Questions
(13)
Which of the following combinations of quantum numbers do not represent permissible
solutions of the Schrodinger wave equation for the hydrogen atom?
A.
B.
C.
(a)
(b)
(c)
(d)
(e)
(14)
ms
9
8
6
8
2
6
-4
-2
-1
-1/2
-1/2
-1/2
A
B
C
B and C
none of the above
orbital
orbit
node
wavefunction
probability function
[Ar]3d34s2
[Ne]5s1
[Ar]3d54s1
[Ar]3s13p6
[Xe]4f145d106s2
Which of the following transitions in the Bohr hydrogen atom model affords emission of the
highest energy photon?
(a)
(b)
(c)
(d)
(e)
(17)
ml
Choose the electron configuration that corresponds to an excited state
(a)
(b)
(c)
(d)
(e)
(16)
l
The places where the value of 2 is zero are called a(n)
(a)
(b)
(c)
(d)
(e)
(15)
n
ni = 1 to nf = 6
ni = 6 to nf = 1
ni = 6 to nf = 3
ni = 3 to nf = 6
ni = 4 to nf = 1
The equation for the second ionization energy of chlorine is
CHE 106
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Fall 2001 Exam Questions
(a)
(b)
(c)
(d)
(e)
(18)
Which of the following elements has the most exothermic electron affinity?
(a)
(b)
(c)
(d)
(e)
(19)
S
Cl
Se
Br
B
In which of the following series are the atoms arranged in order of decreasing first ionization
energy?
(a)
(b)
(c)
(d)
(e)
(20)
Cl2 + 2e- ------> 2ClCl(g) + e- ------> Cl-(g)
Cl(g) -------------> Cl+(g) + e2Cl+(g) ------------> Cl2+(g) + eCl+1(g) ------------> Cl+2(g) + e-
Sr > Ca > Mg
Li > Be > B
O > F > Ne
Ne > Na > Mg
Cl > Br > I
Below is the Born-Haber cycle for the formation of sodium chloride. Which energy change
corresponds to the heat of formation for NaCl?
E
n
e
r
g
y
Na+1(g) +
Cl-1(g)
2
4
Na(g) +
Cl(g)
1
3
Na(s) +
(a)
(b)
(c)
(d)
(e)
CHE 106
1/
2
5
6
Cl2(g)
NaCl(s)
1
2
4
5
6
6
Fall 2001 Exam Questions