Download Chem 1010 Hour Exam 2: Sample Questions for Modules 4, 5, & 6 and more Exams Chemistry in PDF only on Docsity!
You should study your test, study your Handbook modules, and review your drill quizzes BEFORE taking this exam.
When taking it you should do so under exam conditions, i.e. alone, using only a calculator and periodic table, and
waiting until you have completely finished before checking your answers.
1: What is the density of sulfur dioxide gas at 67˚C and 876 torr? (5-4)
A: 13 g/liter B: 2.0 x 101 g/L C: 2.6 g/liter D: 0.22 g/liter E: 0.38 g/liter
2: What is the molecular weight of a gas if 0.60 g of the substance occupies 200 mL at 27 ˚C and
740 torr? (5-4)
A: 90 B: 76 C: 79 D: 68 E: 72
3: What would be the concentration (in M) of the solution produced when 2.0*
ml of 0.30 M hydrobromic acid is
diluted to 1.0*
mL? (4-6,7,8)
A: 0.30 M B: 1.5 M C: 0.060 M D: 40 M E: 0.10 M
4: K-TYPE answer format : Mark a if A,B,C are correct; b if A, C; c if B, D; d if D only; e otherwise.
A: The average velocity of helium atoms is greater at 200˚C than at 100˚C. (5-8)
B: The average kinetic energy of oxygen molecules is greater that of nitrogen dioxide molecules at the same
temperature. (5-8)
C: A sample of oxygen gas at 45˚C and 1.5 atm would be more likely to behave like an ideal gas than would a
sample of oxygen at 45˚C and 2.5 atm. (5-9)
D: If volume and amount of substance are held constant, the temperature in (
o C) and pressure of a gas are
inversely proportional. (5-2)
You should study your test, study your Handbook modules, and review your drill quizzes BEFORE taking this exam.
When taking it you should do so under exam conditions, i.e. alone, using only a calculator and periodic table, and
waiting until you have completely finished before checking your answers.
5: Given: 2 Cl 2
O(g) + 3 O 2
(g) ➞ 4 ClO 2
(g), DH = 249.4 kJ
2 Cl 2
(g) + 1 O 2
(g) ➞ 2 Cl 2
O(g), DH = 160.6 kJ
On the basis of this information, what is the enthatlpy change for the reaction
1 Cl 2
(g) + 2 O 2
(g) ➞ 2 ClO 2
(g)? (6-8)
A: 205.0 kJ B: 88.8 kJ C: -88.8 kJ D: 338.2 kJ E: -71.8 kJ
6: How many mL of 0.20 M calcium hydroxide are needed to completely neutralize 75.0 mL of 0.25 M hydrofluoric acid?
A: 9.4 x 10
mL B: 1.9 x 10
mL C: 3.0 x 10
mL D: 4.7 x 10
mL E: 7.5 x 10
mL
7: Choose the correct statements from the following using K-TYPE answer format. I.E. Mark a if A,B,C are
correct; b if A, C; c if B, D; d if D only; e otherwise.
A: It would be possible to add water to a solution with a concentration of 0.20 M and produce a solution with a
concentration of 0.40 M.
B: A sample of gas which exerts 1 atm in a 1 liter container at 0
o C contains twice as many particles as a sample
which exerts 0.5 atm in a 1 liter container at 0
o C. (5-10)
C: In a 0.1 M potassium chloride solution, the solute is water.
D: According to the kinetic molecular theory of gases, no attractive or repulsive forces operate between gas
molecules. (5-8)
8: For the reaction, N 2
(g) + 2 O 2
(g) ➞ 2 NO 2
(g) , the enthalpy change is 33.9 kJ/mole of NO 2
formed. What is the
enthalpy change (in kJ) when 55.0 grams of oxygen react in this manner?
A: 58.0 kJ B: 117 kJ C: 29.1 kJ D: 94.0 kJ E: 227 kJ
You should study your test, study your Handbook modules, and review your drill quizzes BEFORE taking this exam.
When taking it you should do so under exam conditions, i.e. alone, using only a calculator and periodic table, and
waiting until you have completely finished before checking your answers.
13: On the diagram below: X = 400 J, "A" represents reactants, "B" represents products.
B
A
6X_
5X_
4X_
3X_
2X_
X_
0_
E n t h a l p y
Choose the correct statements
regarding the diagram to the
right using K-TYPE answer
format:
Mark a if A, B, & C are correct.
b if A and C are correct.
c if B and D are correct.
d if D only is correct.
e otherwise.
A: The reaction diagrammed is endothermic. (6-6)
B: The enthalpy change for the reaction to the right is approximately -1600 J. (6-6)
C: Heat (enthalpy) of vaporization is the energy change when a given amount of a substance changes from gas to
liquid at a constant pressure. (6-4)
D: The enthalpy of the reactants is approximately 2000 J. (6-6)
14: Calculate the enthalpy change for the following reaction. (6-10)
CaO (s) + CO 2
(g) ➞ CaCO 3
(s)
A: 2236 kJ B: –178.1 kJ C: 178.1 kJ D: –2236 kJ E: –966.1 kJ
15: A gas initially at 1.68 atm and occupying 16.4 L at 67.0 °C is expanded to 26.4 L and the pressure is decreased to
0.948 atm. What is the final temperature? (5-5)
A: 697 °C B: -154 °C C: 35.8 °C D: 101 °C E: 60.9 °C
16: ( CHALLENGE ) A certain gas diffuses through a long tube in 13.93 minutes. The same volume of hydrogen takes
9.90 minutes to diffuse through the apparatus. What is the molecular weight of the unknown gas? (5-Challenge)
A: 2.84 B: 1.02 C: 1.44 D: 2.00 E: 4.
