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Name: __________________________ Date: _____________
1. Calculate the work, and determine whether it is done by the system or on the system
when 45 J of heat is released and the internal energy increased by 313 J.
A)
B)
C)
D)
E)
+358 J, work done on the system
+268 J, work done on the system
+358 J, work done by the system
+268 J, work done by the system
−268 J, work done by the system
2. Consider this reaction
N2(g) + 3 H2(g)  2 NH3(g) 
H = –92.6 kJ/mol
When 5.00 g of N2 react with excess mol of H2 to form NH3 at 1 atm and a certain
temperature, there is a decrease in volume equal to 49 L. Calculate U for this
reaction. (1 L.atm = 101.3 J).
A)
B)
C)
D)
E)
-11.6 kJ
-97.6 kJ
+97.6 kJ
+43.6 kJ
-14.6 kJ
3. A 22.0 g piece of metal is heated to 100.0°C and placed in 75.0 g H2O at 25°C. If the
final temperature of the metal and water is 27.8°C, what is the specific heat of the metal
in J/g·°C?
A)
B)
C)
D)
E)
0.55
0.16
0.038
12
1.6
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4. Which one of the following reaction corresponds to the standard enthalpy of formation
(ΔHf°) for CuSO4(s)?
A)
B)
C)
D)
E)
Cu(s) + S(s) + 2O2(g) CuSO4(s)
Cu2+(aq) + SO42-(aq) CuSO4(s)
CuO(s) + SO3(g) CuSO4(s)
CuS(s) + 2O2(g) CuSO4(s)
Cu (s) + SO2(g) + O2(g) CuSO4(s)
5. A quantity of 3.00 x 102 mL of 0.950 M HCl is mixed with 3.00 x 102 mL of 0.220 M
Ba(OH)2 in a constant-pressure calorimeter. The initial temperature of both acid and
base solutions is the same at 21.0° C. What is the final temperature of the mixed
solutions?
For the process: H+ (aq) + OH-(aq) → H2O(l) ΔH = -56.2 kJ/mol. Assume that
the specific heat and density of solutions are the same as those of pure water.
A)
B)
C)
D)
E)
24.0° C
18.2° C
52.3° C
25.6° C
36.8° C
6. What is maximum number of electrons that can have the following set of quantum
numbers?
n = 4 and ml = -1
A)
B)
C)
D)
E)
6
8
0
2
14
7. What is the energy of an Avogadro’s number of photons of microwave radiation with a
wavelength 0.122 m?
A)
B)
C)
D)
E)
0.981 J/mol
1.63 x 10-24 J/mol
2.71 x 10-48 J/mol
1.62 x 10-19 J/mol
8.04 J/mol
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8. How many electrons are there in the p orbitals of a vanadium atom (V)?
A)
B)
C)
D)
E)
12
6
3
5
10
9. Calculate the frequency of the light emitted by a hydrogen atom during a transition of its
electron from the n = 4 to the n = 1 principal energy level.
A)
B)
C)
D)
E)
3.08 × 1015 s-1
1.03 × 108 s-1
2.06 × 1014 s-1
1.35 × 10-51 s-1
8.22 × 1014 s-1
10. Calculate the wavelength for a 20Ne+ ion moving with a velocity of 2.00 x 105 m/s.
A)
B)
C)
D)
E)
9.89 x 10-5 nm
1.89 x 10-7 nm
7.15 x 10-9 nm
9.75 x 1012 m
2.08 x 10-4 nm
11. Which of these ground-state ions has at least one unpaired electron?
A) Sc2+
B) V5+
C) Mg2+
D) P3E) S2-
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An element has an electron configuration of 1s22s22p63s2. Which electrons
experience the greatest effective nuclear charge, and which experience the most
shielding, respectively?
12.
Greatest effective :
nuclear charge
A)
B)
C)
D)
E)
1s2 electrons
1s2 electrons
2s2 electrons
3s2 electrons
3s2 electrons
most shielding
:
:
:
:
:
3s2 electrons
2s2 electrons
3s2 electrons
2s2 electrons
2p6 electrons
13. The similar chemical properties of the elements in a given group in the periodic table is
explained by the fact that atoms of these elements have:
A)
B)
C)
D)
E)
the same number of electrons in the valence shell.
similar nuclear structures.
the same number of protons.
the same number of isotopes.
the same number of electrons.
14. How many bonding electrons are there around the central Cl atom in a ClO3- anion in its
"most preferable" Lewis structure?
A)
B)
C)
D)
E)
10
8
12
6
5
15. The first ionization energy for S is lower than the first ionization energy for P because:
A)
B)
C)
D)
E)
S has a stronger electron-electron repulsion in the p orbital.
Hund's rule is violated.
P is more electronegative than S.
P atom is bigger in size than S atom.
S has more unpaired electrons than P.
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16. Calculate the lattice energy of CaCl2 using the following data.
IE1(Ca) = 590 kJ/mol,
IE2 (Ca) = 1145 kJ/mol,
H f [Ca(g)]=179.3 kJ/mol,
H f [Cl(g)] = 121.7 kJ/mol,
H f [CaCl2(s)] = 794.6 kJ/mol,
EA(Cl) = 349 kJ/mol,
A)
B)
C)
D)
E)
2254
1287
1254
1145
2154
17. Arrange calcium, rubidium, sulfur, and arsenic in order of decreasing electronegativity.
A)
B)
C)
D)
E)
S > As > Ca > Rb
S > As > Rb > Ca
As > S > Rb > Ca
As > S > Ca > Rb
Ca > S > As > Rb
18. Estimate the enthalpy of combustion reaction of methane (CH4)?
(Note: You need to write and balance the reaction between CH4 and O2).
Given:
A)
B)
C)
D)
E)
C-H 414 kJ/mol;
C=O 799 kJ/mol; and
O=O 498.7 kJ/mol;
H-O 460. kJ/mol.
-785 kJ/mol
+785 kJ/mol
-370 kJ/mol
+370 kJ/mol
+550 kJ/mol
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19. Which one of the following follows the octet rule?
A)
B)
C)
D)
E)
CO2
NO2
ClO2
BF3
SF6
20. In the following Lewis structure for ClO3F, chlorine has a formal charge of ____ and an
oxidation number of ____.
A)
B)
C)
D)
E)
1, 7
7, -1
1, 1
1, -1
7, -7
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Answer Key
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A
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A
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