S.Gammon Chemistry 121 Sample Chemistry 121 Final Exam Questions

S.Gammon Chemistry 121
Sample Chemistry 121 Final Exam Questions
DO NOT USE THIS AS YOUR SOLE MEANS OF PREPARATION FOR THE FINAL
1.
When the equation below is balanced, what is the coefficient for H2O?
PCl5
a.
2.
8
b.
+
OH-
2
c.
7
*b. 8
5
9
d.
10
e.
11
d.
e.
2.28 x 1024
4.40 x 1024
The molecular geometry of the ICl3 molecule is:
trigonal bipyramidal
trigonal bipyramidal
trigonal planar
d. linear
*e. T-shaped
The formula for calcium phosphate is:
d.
e.
Ca3P2
Ca3(PO3)2
How many moles of Fe are produced when 100. g of Fe2O3 are reacted according to the following
equation?
2Al
a.
8.
H2O
dumbbell shaped
conical
c.
a. CaPO4
*b. Ca3(PO4)2
c. Ca2(PO4)3
7.
e.
+
Calculate the number of atoms of hydrogen in 44.4 mL of ethyl alcohol (C2H5OH) which has a
density of 0.789 g/mL.
a.
b.
c.
6.
*d. 4
d.
e.
a. 4.58 x 1023
b. 1.37 X 1024
*c. 2.74 x 1024
5.
3
Cl-
A compound composed of only C, H, and O has an approximate molecular weight of 167. By
combustion analysis it is found to have 57.83% carbon and 3.64% hydrogen. How many atoms of C
does the molecule contain.
a.
4.
PO43- +
All s-orbitals are:
a. circular
b. pear shaped
*c. spherical
3.
===>
0.313 mol
+
Fe2O3 ==>
b.
0.626 mol
Al2O3 +
*c. 1.25 mol
2Fe
d.
1.60 mol
e.
3.19 mol
Chemical reactions of atoms under normal laboratory conditions primarily involve changes in:
a. neutrons
b. protons
*c. electrons
d.
e.
protons and electrons
protons, neutrons, and electrons
S.Gammon Chemistry 121
9.
A 100. mL solution of the base Ca(OH)2 is titrated with 48.8 mL of 5.00 x 10-2 M HBr to reach the
end point. Calculate the concentration of Ca(OH)2 in the solution.
a. 4.88 X 10-2 M
b. 2.44 x 10-2 M
*c. 1.22 x 10-2 M
d.
e.
1.00 x 10-2 M
none of the above
10. What is the mass of 3.00 moles of ethanol, C2H6O?
a. 4.99 x 10-24 g
*b. 138 g
c. 6.52 x 10-2 g
d.
e.
50 g
1.81 x 1024 g
11. Which of the following is the largest?
a.
F+7
b.
Li
*c. K
d.
Ga2+
e.
C
12. How many carbon atoms are contained in 6.00 g of C6H6?
a. 6.02 x 1023
*b. 2.78 x 1023
c. 0.0769
d.
e.
1.28 x 10-25
4.63 x 1022
13. The species 195Pt2+ has how many neutrons and protons?
a. 195 neutrons and 78 protons
b. 117 neutrons and 76 protons
*c. 117 neutrons and 78 protons
d.
e.
76 neutrons and 195 protons
78 neutrons and 117 protons
14. How many resonance structures are required to correctly describe the bonding in NO3-.
a.
1
b.
2
*c. 3
d.
4
e.
5
d.
O3
15. Which of the following molecules is linear?
*a. I3-
b.
H2S
c.
CH22-
e.
PH3
16. A 0.519 g sample of KMnO4 is dissolved in enough water to make 450. mL of solution. The
concentration KMnO4 is:
a. 1.15 M
*b. 7.26 x 10-3 M
c. 1.04 x 10-2 M
d.
e.
4.16 x 10-2M
4.00 x 10-3 M
17. Which of the following molecules has no dipole moment?
a.
HF
b.
NH3
c.
H2S
d.
CO
*e. SF6
S.Gammon Chemistry 121
18. What are the O-C-O bond angles in CO32-?
a.
180o
*b. 120o
c.
109.5o
d.
90o
c.
Zn2O3
d.
Zn3O2
e.
54.5o
19. The formula for zinc oxide is:
a.
Zn2O
*b. ZnO
e.
ZnO2
20. For the reaction
6AlBr3 + 3CaCr2O7 + 14H3PO4 ==> 9Br2 + 6CrPO4 + 3Ca3(PO4)2 + 2K3PO4 + 21H2O
how many moles of Ca3(PO4)2 are produced when 3.0 moles of AlBr3, 2.5 moles of CaCr2O7 and 8.0
moles of H3PO4 are mixed and reacted. Assume that the %yield of the reaction is 100%.
a.
3.0
b.
1.7
c.
2.5
d.
3.2
*e. 1.5
21. How many of the following are oxidation-reduction reactions?
a.
NaOH + HCl ===> NaCl
*Cu + 2AgNO3 ===> 2Ag
Mg(OH)2 ===> MgO +
*N2 + 3H2 ===> 2NH3
+ H2O
+ Cu(NO3)2
H2O
0
d.
b.
1
*c. 2
3
e.
4
22. Which statement about N2 is false?
a.
*b.
c.
d.
e.
It is a gas at room temperature.
The formal charge is +3 on N and - 3 on the other.
It has a triple bond.
It can combine with H2 to form NH3.
It has two sets of lone pair electrons.
23. Aqueous solution of sodium sulfide and copper (II) chloride are mixed together. Which statement is
correct?
a.
b.
*c.
d.
e.
Both NaCl and CuS precipitate from solution.
No precipitate forms.
CuS will precipitate from solution.
NaCl will precipitate form solution.
No reaction will occur.
S.Gammon Chemistry 121
24. Iron (II) sulfate reacts with potassium hydroxide in aqueous solution to form a precipitate. The net
ionic equation for this reaction is
a.
b.
Fe2+
2K+
c. 2Fe3+
*d. Fe2+
e. K+
+
SO42SO423SO422OH-
===>
+
Fe2+
===>
+
+
+
===>
FeSO4
===>
K2SO4
===>
Fe2(SO4)3
Fe(OH)2
Fe3+
25. If two moles of C6H12O6 are reacted with 18 mol of O2 in the following reaction
C6H12O6
+
6O2 ===> 6CO2
+
6H2O
how much reactant will be left over?
a.
b.
c.
d.
*e..
0 mol of C6H12O6 and 16 mol of O2
1 mol of C6H12O6 and 12 mol of O2
3 mol of C6H12O6 and 12 mol of O2
2 mol of C6H12O6 and 0 mol of O2
0 mol of C6H12O6 and 6 mol of O2
26. What is the molecular geometry of XeF4?
a. linear
b. tetrahedral
*c. square planar
d.
e.
octahedral
trigonal pyramidal
27. For the reaction of Cs(s) with F2(g) , which of the following statements is FALSE?
*a. Cs is the elctron acceptor.
b. the product is the ionic compound CsF.
c. fluorine is the elctron acceptor.
d.
e.
Cs+ ions are formed.
all of the above are true.
28. Which of the following ions is most likely to form an insoluble chloride?
a.
K+
b.
Li+
*c. Pb2+
d.
S2-
e.
F-
29. The effect of inner electrons on the nuclear charge "felt" by the valence electrons is called
*a. shielding
b. repulsion
c. configuration
d.
e.
Aufbau
lattice energy
30. Calculate the number of moles of In2S2 in 2.2 kg of In2S2.
a.
b.
c.
7.5 x 1023 mol
7.5 x 10-3mol
7.5 x 103 mol
d. 7.5 x 10-6 mol
*e. 7.5 mol
S.Gammon Chemistry 121
31. The balanced molecular equation for the neutralization of sodium hydroxide with sulfuric acid, the
products are:
a.
b.
c.
NaSO4 +
NaSO3 +
2NaSO4 +
H2O
2H2O
H2O
d. Na2S +
*e. Na2SO4 +
2H2O
2H2O
32. Which of the following statements is false?
a.
b.
c.
d.
e.
A sodium atom has a smaller radius than a potassium atom.
A neon atom has a smaller radius than an oxygen atom.
A fluorine atom has a smaller first ionization energy than an oxygen atom.
A cesium atom has a smaller first ionization energy than a lithium atom.
Chlorine is more electronegative than cesium.
33. Which of the following atoms has 3 electrons in p orbitals in its valence shell?
a.
Ba
b.
Al
c.
V
*d. Bi
e.
None of these
34. What volume of 12.0 M nitric acid is required to prepare 6.00 L of 0.100 M nitric acid?
a.
1.20 L
b.
1.00 L
c.
0.500 L
*d. 0.0500 L
e.
0.0200 L
35. In the formation of ionic solids from elements, the "big payback" in energy that usually compensates
for the energy required in the process.
a.
b.
c.
electron repulsion
ionization energy
heat of vaporization
*d. lattice energy
e. none of these
36. Which of the following salts is insoluble in water?
a.
Na2S
b.
K3PO4
c.
Pb(NO3)2
d.
CaCl2
*e. all are soluble
37. When 25.0 mL of H2SO4 solution was completely neutralized in a titration with 0.0500 M NaOH
solution, 18.3 mL of the base was required. What was the molarity of the H2SO4 solution?
a.
b.
c.
0.300 M
0.0750 M
0.450 M
d. 0.148 M
*e. 0.0183 M
38. In the reaction shown below, what species is oxidized?
2NaI
a.
Na+
+
Br2 ===>
*b. I-
c.
2NaBr +
I2
Br2
d.
Br-
e.
I2
39. For which compound does 0.256 moles weigh 12g?
a.
C2H4O
b.
CO2
*c. CH3Cl
d.
C2H6
e.
none
S.Gammon Chemistry 121
40. The balanced equation for the neutralization of phosphoric acid with calcium hydroxide shows
_____________ molecules of water produced. Calcium phosphate is the other product (you come up
with the correct reaction).
a.
0
*b. 3
c.
4
d.
5
*e. 6
41. A 6.32g sample of potassium chlorate was decomposed according to the following equation:
2KClO3 ====> 2KCl + 3O2
How many moles of oxygen are formed?
a.
1.65 moles
b.
0.051 moles
c.
0.0344 molesd.
*d. 0.0774 mole e.
0.243 moles
42. Which of the following metric relationships is incorrect?
a. 1 micrometer = 10-6 meters
b. 1 megagram = 106 grams
*c. 1 millimeter = 103 meters
d.
e.
1 kilogram = 103 grams
100 centimeters = 1 meter
43. Which of the following molecules contains an sp2-sp2 sigma bond?
a.
CH4
b.
C2H2
*c. C2H4
d.
C2H6
e.
none of them (a-d)
44. Given the following bond energies in KJ/mol estimate the ∆H (in KJ) for the reaction
H
H--O--O--H
+
H
H--C--O--H
H
Bond
C-C
C=C
C-O
C=O
C-H
O-H
O-O
*a. -343
b.
-199
+ 2 H--O--H
C=O
H
Energy (kJ)
347
614
358
799
413
463
146
c.
-105
d.
+199
e.
+343
45. A sample of metal has a mass of 27.24 g and a volume of 2.2 mL. What is the correct way to report
value of its density?
a.
b.
c.
12.382 g/mL
0.081 g/mL
12.38 g/mL
d. 0.876 g/mL
*e. 12 g/mL
46. Which set contains only diatomic elements?
I. Silver, iron, lead, mercury
II. Bromine, oxygen, fluorine, nitrogen
III. Sodium, lithium, potassium, cesium
a. I
*b. II
c. III
d. I and II
e.
I, II, and III
S.Gammon Chemistry 121
47. What mass of styrene (MW = 104.1 g/mol) will contain 4.50 x 1020 molecules of styrene?
a. 7.48 x 10-4 g
b. 7.48 x 10-3 g
*c. 7.78 x 10-2 g
d.
e.
0.00778 g
7.48 x 104 g
48. The Claus reactions, shown below, are used to generate elemental sulfur from hydrogen sulfide.
2H2S + 3O2 ===> 2SO2 + 2H2O
SO2 + 2H2S ====> 3S + 2H2O
How many grams of sulfur is produced from 48.0 grams of O2?
a.
16.0 g
b.
32.1 g
c.
48.1 g
*d. 96.2 g
e.
104.4 g
32
49. The sulfur isotope, 16S2-, has
a.
b.
c.
16 protons, 16 electrons, and 16 neutrons.
16 protons, 16 electrons, and 32 neutrons.
32 protons, 32 electrons, and 16 neutrons.
*d. 16 protons, 18 electrons, and 16 neutrons.
e. 16 protons, 14 electrons, and 16 neutrons.
50. The molarity of Cl- available in 110. mL of a solution containing 5.55 g of CaCl2 is:
a.
0.00550 M
b.
0.455 M
c.
0.668 M
*d. 0.909 M
e.
50.5 M