Download chem 155 trial questions

CHEM 155 TRIAL QUESTIONS
1. How many states of matter exist?
a. 1
b. 2
c. 3
d. 4
d. 5
2.What state of matter are the particles the farthest apart?
a. Solid
b. Liquid
c. Gas
d. Plasma
3.
a.
b.
c.
d.
4.
a.
b.
c.
d.
What state of matter are the particles the closest together?
Liquid
Gas
Plasma
Solid
What state of matter are the particles moving in one direction?
solid
Liquid
Gas
Plasma
5. Purity of a substance can be estimated through
a. boiling points
b. melting points
c. None of These
d. Both A and B
6. The melting point of ice is the same as the freezing point of water.
a. True
b. False
7. When water vaporizes at room temperature, it changes into
a. Water vapour
b. Fog
c. Steam
d. Ice
8. Liquids have the ability to flow because
a. their particles can slide over each other.
b. their particles are arranged in a regular pattern.
c. their particles are very far apart.
d.There are strong forces of attraction between the particles.
9. When two gases mix together, they are said to
a. Condense
b. Evaporate
c. Diffuse
d. Melt
10. Which one of the following is not a property of gases?
a. They have a definite mass.
b. They can diffuse.
c. They have no definite shape.
d. They have a definite volume.
11. Which one of the following states of matter can easily be compressed?
a. Gas or liquid
b. Gas
c. Liquid
d. Solid
12. Dry ice is used in fire extinguishers. The dry ice is stored in the cylinder in a solid form.
When sprayed on a fire it quickly changes into the gas known as carbon dioxide (CO2).
What is this change of state called?
a. Evaporation
b. Sublimation
c. Condensation
d.. Distillation
13. A gas will approach ideal behaviour at
a. High temperature,low pressure
b. Low temperature,high pressure
c. Low temperature, low pressure
d. High temperature,high pressure
14. If both temperature and volume of a gas doubled, the pressure?
a. Also doubled
b. Is reduced to half
c. Remain unchanged
d. increases four times
15. A mixture of gas expands from 0.03 m3 to 0.06 m3 at a constant pressure of 1 MPa and
absorbs 84 kJ of heat during the process. The change in internal energy of the mixture is
a. 54 kJ
b. 84 kJ
c. 114 kJ
d. 30 kJ
16. In an irreversible process, there is a
a. no loss of heat
b. gain of heat
c. no gain of heat
d. loss of heat
17. The measurement of a thermodynamic property known as temperature is based on
a. none of these
b. Second law of thermodynamics
c. Zeroth law of thermodynamics
d. First law of thermodynamics
18. In an isothermal process
a. there is no change in internal energy
b. there is no change in temperature
c. there is no change in enthalpy
d. all of these
19. When two bodies are in thermal equilibrium with a third body, they are also in thermal
equilibrium with each other. This statement is called
a. Zeroth law of thermodynamics
b. Second law of thermodynamics
c. First law of thermodynamics
d. Kelvin Planck's law
20. The area under the temperature-entropy curve (T – s curve) of any thermodynamic process
represents
a. heat rejected
b. none of these
c. heat absorbed
d. either heat absorbed or heat rejected
21. Which of the following is the correct statement of the second law of thermodynamics?
a. It is impossible to transfer heat from a body at a lower temperature to a higher
temperature, without the aid of an external source.
b.
all of the above
c. It is impossible to construct an engine working on a cyclic process, whose sole purpose is to
convert heat energy into work.
d. There is a definite amount of mechanical energy, which can be obtained from a given
quantity of heat energy.
22. Workdone in a free expansion process is
a. zero
b maximum
c. minimum
d. positive
23. The processes occurring in open system which permit the transfer of mass to and from the
system, are known as
a. non-flow processes
b. adiabatic processes
c. none of these
d. flow processes
24. The amount of heat required to raise the temperature of the unit mass of gas through one
degree at constant volume, is called
a. specific heat at constant volume
b. specific heat at constant pressure
c. none of these
d. kilo Joule
25. An adiabatic process is one in which
a. no heat enters or leaves the gas
b. the change in internal energy is equal to the mechanical work done
c. the temperature of the gas changes
d. all of the above
26. The sum of internal energy (U) and the product of pressure and volume (p.v) is known as
a. workdone
b. none of these
c. enthalpy
d. entropy
27. A series of operations, which takes place in a certain order and restore the initial
conditions at the end, is known as
a. reversible cycle
b. irreversible cycle
c. thermodynamic cycle
d. none of these
28. An isothermal process is governed by
a. Avogadro's law
b. Charles' law
c. Gay-Lussac law
d. Boyle's law
29. The entropy of water at 0°C is assumed to be
a. 1
b. -1
c. 0
d. 2
30. A process, in which the temperature of the working substance remains constant during its
expansion or compression, is called
a. isothermal process
b. hyperbolic process
c. polytropic process
d. adiabatic process
31. The specific heat of water is
a. none of these
b. 4.187
c. 1.817
d. 2512
32. Which of the following is an intensive property of a thermodynamic system?
a. Mass
b. Temperature
c. Energy
d. Volume
33. Which one of the following definitions best describes the concept of work?
a. the flow of energy from one object or substance to another due to a difference in
temperature
b. the flow of energy from one body to another through uniform molecular motion
c.
d.
the force associated with molecular motion
the random motion of molecules in a gas at low pressure
34. An isolated system is best described by which one of the following statements?
a. Neither matter nor heat can pass into or out of the system
b. The system has a boundary which allows heat to be transferred but does not allow material
to pass into or out of the system
c. The system has a diathermic boundary
d. A system which has reached thermal equilibrium with its surroundings
35. Which one of the following statements describes a path function?
a. A property of a system that depends only on the current state of the system, not on the path
the system took to reach that state
b. A property of a system that depends on the path taken between the initial and final states
c. The sum of kinetic and potential energy contained in a substance
d. The heat energy absorbed by a system at constant pressure
36. Consider the following thermodynamic properties.
i) work done on a system
ii) heat absorbed
iii) entropy
iv) enthalpy
Which of these properties are state functions?
a.
b.
c.
d.
i) and ii) only
i) and iii) only
i) only
iii) and iv) only
37. Which of the following statements best describes the Second Law of Thermodynamics?
a. The internal energy of the universe is constant.
b. Energy can be neither created nor destroyed.
c. When an isolated system undergoes a spontaneous change, the entropy of the system will
increase.
d. At absolute zero, the entropy of a perfect crystal is considered to be zero.
38. A drug used to treat hypertension undergoes a decomposition reaction to give an
insoluble product. Calculate the temperature at which this reaction becomes spontaneous if the
enthalpy of the reaction at 298 K is 51 kJ mol-1 and the entropy of the reaction at this
temperature is 118.74 J K-1 mol-1.
a.
b.
c.
d.
430 K
2 300 K
0.5 K
430oC
39. Which one of the following equations defines the enthalpy of reaction, ΔH, for a reaction
occurring at constant pressure that does expansion work? All terms have their usual meanings.
a.
b.
c.
d.
ΔH = ΔU
ΔH = ΔU + pΔV
ΔH = ΔG - TΔS
ΔH = q + w
40. Which of the following statements will always apply when a reversible chemical reaction
has attained equilibrium?
a.
b.
c.
d.
All reactants will convert to products
The reaction proceeds alternately in the forward and reverse directions
The Gibbs free energy of the system reaches a minimum
The forward reaction will dominate over the reverse reaction
41. Which one of the following is an expression of the van't Hoff equation?
a.
b.
c.
d.
ln K = - ΔHθ / RT + ΔSθ /R
ΔH(T2) = ΔH(T1) + ΔCp(T2 - T1)
ΔGθ = ΔHθ - TΔSθ
ΔU = q + w
42. What law asserts that energy is a thermodynamic property?
A. First law of Thermodynamics
B. Second law of Thermodynamics
C. Third law of Thermodynamics
D. Zeroth law of Thermodynamics
43. What law asserts that energy has quality as well as quantity?
A. First law of Thermodynamics
B. Second law of Thermodynamics
C. Third law of Thermodynamics
D. Zeroth law of Thermodynamics
44. The macroscopic approach to the study of thermodynamics does not require a knowledge
of the behavior of individual particles is called _____.
A. Dynamic thermodynamics
B. Static thermodynamics
C. Statistical thermodynamics
D. Classical thermodynamics
45. What is the more elaborate approach to the study of thermodynamics and based on the
average behavior of large groups of individual particles?
A. Dynamic thermodynamics
B. Static thermodynamics
C. Statistical thermodynamics
D. Classical thermodynamics
46. What is a defined region in space chosen for study?
A. Surroundings
B. System
C. Boundary
D. Volume
47. The first law of thermodynamics is based on which of the following principles?
A. Conservation of mass
B. Conservation of energy
C. Action and reaction
D. The entropy-temperature relationship
48. What is the mass or region outside the system called?
A. Surroundings
B. Boundary
C. Volume
D. Environment
49. What is the real or imaginary surface that separates the system from its surroundings?
A. Division
B. Wall
C. Boundary
D. Interface
50. A system which consists of fixed amount of mass and no mass can cross its boundary
called _____.
A. Equilibrium system
B. Thermal equilibrium system
C. Open system
D. Closed system
51. A system in which even energy is not allowed to cross the boundary is called ____.
A. Closed system
B. Exclusive system
C. Isolated system
D. Special system
52. A system in which there is a flow of mass is known as _____.
A. Equilibrium system
B. Isolated system
C. Open system
D. Closed system
53. Open system usually encloses which of the following devices?
A. Compressor
B. Turbine
C. Nozzle
D. All of the above
54. The boundaries of a control volume, which may either real or imaginary is called _____.
A. Control boundary
B. Control system
C. Interface
D. Control surface
55. Any characteristic of a thermodynamics system is called a _____.
A. Property
B. Process
C. Phase
D. Cycle
56. How are thermodynamic properties classified?
A. Physical and chemical
B. Intensive and extensive
C. Real and imaginary
D. Homogeneous and heterogeneous
57. The thermodynamic properties that are independent on the size of the system is called
_____.
A. Extensive property
B. Intensive property
C. Open property
D. Closed property
58. The thermodynamic properties that are dependent on the size or extent of the system is
called _____.
A. Extensive property
B. Intensive property
C. Open property
D. Closed property
59. Which is NOT an intensive property of thermodynamics?
A. Temperature
B. Mass
C. Pressure
D. Density
60. Which is NOT an extensive property of thermodynamics?
A. Density
B. Mass
C. Volume
D. Energy
61. Extensive properties per unit mass are called _____.
A. Specific properties
B. Relative properties
C. Unit properties
D. Phase properties
62. A system is in ______ equilibrium if the temperature is the same throughout the entire
system.
A. Static
B. Thermal
C. Mechanical
D. Phase
63. A system is in ______ equilibrium if there is no change in pressure at any point of the
system with time.
A. Pressure
B. Thermal
C. Mechanical
D. Phase
64. If a system involves two phases, it is in ______ equilibrium when the mass of each phase
reaches an equilibrium level and stays there.
A. Chemical
B. Thermal
C. Mechanical
D. Phase
65. A system is in ______ equilibrium of its chemical composition does not change with time,
i.e., no chemical reaction occurs.
A. Chemical
B. Thermal
C. Mechanical
D. Phase
66. “The state of a simple compressible system is completely specified by two independent,
intensive properties”. This is known as ______.
A. Equilibrium postulate
B. State postulate
C. Environment postulate
D. Compressible system postulate
67. What is the unit of the total energy of the system?
A. Kj
B. Kj/Kg
C. Kg
D. g
68. Without electrical, mechanical, gravitational, surface tension and motion effects, a system
is called _____ system.
A. Simple
B. Simple compressible
C. Compressible
D. Independent
69. What refers to any change that a system undergoes from one equilibrium state to another
equilibrium state?
A. Process
B. Path
C. Phase
D. Cycle
70. What refers to the series of state through which a system passes during a process?
A. Path
B. Phase
C. Cycle
D. Direction
71. How many independent properties are required to completely fix the equilibrium state of a
pure gaseous compound?
A. 4
B. 3
C. 2
D. 1
72. Three moles of an ideal gas (Cv = 5cal K-1 mol-1) at 10 atm and 0 are converted to 2.0atm
at 50°. The ∆E for the process is
A.150 cal
B. 300 cal
C. 750 cal
D. 1500 cal
73. A closed system may refer to ______.
A. Control mass
B. Control volume
C. Control energy
D. Control temperature
74. An open system may refer to ______.
A. Control mass
B. Control volume
C. Control energy
D. Control temperature
75. A system is said to be in thermodynamic equilibrium if it maintains ______ equilibrium.
A. Mechanical and phase
B. Thermal and chemical
C. Thermal, mechanical and chemical
D. Thermal, phase, mechanical and chemical
76. What is a process with identical end states called?
A. Cycle
B. Path
C. Phase
D. Either path or phase
77. What is a process during which the temperature remains constant?
A. Isobaric process
B. Isothermal process
C. Isochoric process
D. Isometric process
78. What is a process during which the pressure remains constant?
A. Isobaric process
B. Isothermal process
C. Isochoric process
D. Isometric process
79. What is a process during which the specific volume remains constant?
A. Isobaric process
B. Isothermal process
C. Isochoric or isometric process
D. Isovolumetric process
80. The prefix “iso” used to designate a process means ______.
A. Cannot be interchanged
B. Remains constant
C. Approximately equal
D. Slight difference
81. What does the term “steady” implies?
A. No change with volume
B. No change with time
C. No change with location
D. No change with mass
82. What does the tem “uniform” implies?
A. No change with volume
B. No change with time
C. No change with location
D. No change with mass
83. What is defined as a process during which a fluid flows through a control volume
steadily?
A. Transient-flow process
B. Steady and uniform process
C. Uniform-flow process
D. Steady-flow process
84. The sum of all the microscopic form of energy is called _____.
A. Total energy
B. Internal energy
C. System energy
D. Phase energy
85. What type of system energy is related to the molecular structure of a system?
A. Macroscopic form of energy
B. Microscopic form of energy
C. Internal energy
D. External energy
86. What form of energy refers to those a system possesses as a whole with respect to some
outside reference frame, such as potential and kinetic energies?
A. Macroscopic form of energy
B. Microscopic form of energy
C. Internal energy
D. External energy
87. Who coined the word “energy” in 1807?
A. William Rankine
B. Rudolph Clausius
C. Lord Kelvin
D. Thomas Young
88. The molecules of a gas moving through space with some velocity possesses what kind of
energy?
A. Translational energy
B. Spin energy
C. Rotational kinetic energy
D. Sensible energy
89. The electrons in an atom which rotate about the nucleus possess what kind of energy?
A. Translational energy
B. Spin energy
C. Rotational kinetic energy
D. Sensible energy
90. A gas expands from 10 litres to 20 litres against a constant external pressure of 10atm. The
pressure volume work done by the system is
i.100 lit atm
ii.-100 lit atm
iii.10 lit atm
iv.-10 lit atm
91. The mathematical relation for the first law of thermodynamics is
A. ∆E = q-w
B. ∆E = 0 for a cyclic process
C. ∆E = q for an isochoric process
D. all of these
92 The change in enthalpy of a system is measured by measuring
A.
B.
C.
D.
Heat of the process at constant volume
Heat of the process at constant temperature
Heat of the process at constant pressure
None of these
93. The enthalpy change, ∆H of a process is given by the relation
A. ∆H = ∆E + p ∆v
B. ∆H = ∆E + ∆nRT
C. ∆H = ∆E + w
D. 𝑎𝑙𝑙 𝑜𝑓 𝑡ℎ𝑒𝑠𝑒
94. Which of the following relations is true?
A. Cp > Cv
B. CV > CP
C. Cp = Cv
D. Cp = Cv = 0
95. The heat capacity of constant pressure is related to heat capacity at constant volume by the
relation
A. Cp – R = Cv
B. Cv – R = Cp
C. Cp – Cv = R
D. R - Cp = Cv
96. The enthalpy change of a reaction is independent of
A. state of the reactants and products
B. nature of the reactants and products
C. initial and final enthalpy change of the reaction
D. different intermediate reaction
97. One mole of an ideal gas at 300K is expanded isothermally from 1 litre volume to 10 litre
volume. ∆E for this process is (R= 2 cal K-1 mol-1)
A. 300 cal
B. 600 cal
C.1200 cal
D.0 cal
98. A system absorbs 100kJ heat and performs 50kJ work on the surroundings. The increase
in internal energy of the system is
A. 50 kJ
B. 100kJ
C. 150kJ
D. 5000Kj
99. For the reaction H2 + I2
A. ∆E + 2RT
B. ∆E = 2RT
C. ∆E
D. ∆E + RT
2HI, ∆𝐻 IS EQUAL TO
100. The work done when 1 mole of a gas expands reversibly and isothermally from 5atm to
1atm at 300K is
A. -4015 J
B. +4015 J
C. zero
D. 150 J