Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

ChELE > Thermodynamics > Flashcards

Thermodynamics Flashcards

1
Q

is a branch of physical science that deals with the study of interrelation of various
forms of energy.

A

Thermodynamics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Work done ON the system

a. Endergonic
b. Exergonic
c. Endothermoc
d. Exothermic

A

Endergonic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Work done BY the system

a. Endergonic
b. Exergonic
c. Endothermoc
d. Exothermic

A

Exergonic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

___________ reactions are chemical reactions in which the reactants absorb heat energy from the surroundings to form products

a. Endergonic
b. Exergonic
c. Endothermoc
d. Exothermic

A

Endothermic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

is a thermodynamic process or reaction that releases energy from the system to its surroundings

a. Endergonic
b. Exergonic
c. Endothermoc
d. Exothermic

A

Exothermic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Which law is the basis for the manufacture of thermometers

A

Zeroth Law of thermodynamics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

The credit for formulating the Zeroth law goes to _______

A

Ralph Howard Fowler

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Type of system that allows transfer of both matter and energy

A

Open System/Control Volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

type of system that allows exchange of energy only

A

Closed System

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

type of system that allows neither transfer of matter nor energy

A

Isolated System

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

real/imaginary or fixed/moving surface that separates the system from its surroundings and where exchange of matter or energy takes place

A

Boundary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

a state in which (a) the properties of the system do not vary with time, (b) the system is uniform where there is no internal temperature, pressure, concentration or velocity gradient, (c) the net flows of heat, mass or work between the system and its surroundings are zero and (d) the net rate of all chemical reactions is zero

A

Equilibrium state

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

a thermally-insulating boundary in which no change of state is observed even though two objects at different temperatures are brought into contact (a boundary that does not let heat to transfer)

A

Adiabatic Boundary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

a thermally-conducting boundary in which a change of state is observed when two objects of different temperatures are brought into
contact (a boundary that allows heat to transfer)

A

Diathermic Boundary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

state that exists between two subsystems of equal
pressure (there is no unbalanced force/ pressure gradient on the system)

A

Mechanical Equilibrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

state that exists between two subsystems of equal temperature

A

Thermal Equilibrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

any change that undergoes within a system that causes shift from one equilibrium state to another

A

Process

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

a sufficiently slow process that allows the system to internally adjust so that the properties in one part does not change faster than the other parts

A

Quasi static/Quasi-equilibrium process

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

process where a fluid flows through a control volume and the fluid properties can change from point to point within the control volume, however at any fixed point these properties remain constant during the entire process

A

Steady flow process

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

a thermodynamic process in which the net rate of heat transfer to and from the system is zero

A

Adiabatic/Isocaloric process

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Constant temperature process

A

Isothermal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Constant pressure process

A

Isobaric

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Constant volume process

A

Isochoric/Isometric

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

_______ functions that depend on the current state of the system and not on how the system reaches that state

A

State/point functions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

______ functions that depend on the path followed during a process

A

Path functions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

form of energy transferred from one body to another by virtue of a temperature difference

A

Heat (Q)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

form of energy that results in the motion of a body by virtue of an opposing force; energy transfer associated with a force acting through a distance

A

Work (W)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What are the THREE Mechanical forms of Work

A
  1. Shaft
  2. Spring
  3. Surface Tension
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

The DISORDERLY or RANDOM molecular motion for transfer of energy as heat is also called ______ motion of molecules

A

Thermal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

When work is done BY the system, molecules move in a/an ________ way

A

organized/orderly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

This refers to the energy of the system as a bulk which can be associated with the velocity and location of its center of mass

A

External Energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

It is the energy due to the translational motion of the system relative to some point of reference or to the rotation of the system about an axis

A

Kinetic Energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

It is the energy due to the position of the system in a potential field such as electromagnetic field or gravitational field

A

Potential Energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

“Energy of the universe is constant”

A

1st law of thermo

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

“Energy can neither be created nor destroyed but can only be changed from one form to another”

A

Law of Conservation of Energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

“If body A is in thermal equilibrium with body B, and the body B is in thermal equilibrium with body C, then body A is in thermal equilibrium with body C.”

A

Zeroth Law of thermo

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

principle of thermal equilibrium between thermodynamic systems in contact

A

Zeroth Law of Thermo

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

The first explicit statement of the 1st Law of Thermodynamics was given by _______

A

Rudolf Julius Emmanuel Clausius

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

refers to the total energy of the system in the molecular level which can be due to the motion of molecules relative to the center of mass of the system, or to the rotational and vibrational motion and the electromagnetic interactions of the molecules, or to the motion and interaction of the atomic and subatomic components of the molecules

A

Internal Energy (U)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

energy associated with the kinetic energy of the molecules as it moves at a certain velocity through space

A

Translational KE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

energy associated with the back-and-forth motion of the atoms in a polyatomic molecule about their common center of mass

A

Vibrational KE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

energy associated with the rotation of the atoms in a polyatomic molecule about an axis

A

Rotational KE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

energy associated with the rotation of the subatomic particles about their axes

A

Spin Energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

states that the total kinetic energy of a system is shared equally among its independent components once the system attains thermal equilibrium

A

Equipartition Theorem of energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

It is the measure of total energy of a thermodynamic system

A

Enthalpy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Describes the temperature change of a fluid when it is forced to flow through a valve or porous plug adiabatically

A

Joule-Thompson effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Involves measurement of heat involved in a chemical reaction or physical change

A

Calorimetry

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

What are the TWO TYPES of Calorimeter

A
  1. Open Type
  2. Bomb Type
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Type of Calorimeter that operates at constant pressure

A

Open Type

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Type of Calorimeter that operates at constant volume

A

Bomb Type

51
Q

A device that INCREASES the VELOCITY of the fluid resulting to a DECREASE in its PRESSURE

A

Nozzle

52
Q

A device that DECREASES the VELOCITY of the fluid resulting to an INCREASE in its PRESSURE

A

Diffuser

53
Q

Compressors, fans, and pumps are devices used to ____________ the pressure of a fluid by the supply of work through a rotating shaft.

a. Increase
b. Decrease
c. Both
d. Hatdog

A

a. Increase

54
Q

________ are used to transport a gas by increasing its pressure slightly

a. Compressors
b. Fans
c. Pumps
d. None of the above

A

b. Fans

55
Q

Compressors and pumps are devices capable of increasing the pressure of ___________.

a. Gases only
b. Liquids only
c. Both
d. Solids

A

c. Both

56
Q

Refers to any flow-restricting device such as an adjustable valve, porous plug or a capillary tube

A

Throttling Valves

57
Q

T or F

Throttling device operates at constant enthalpy

A

True

58
Q

What is constant enthalpy

A

Isenthalpic

59
Q

“All processes in nature tend to occur only with an increase in entropy and that the direction of change is always such as to lead to the increase in entropy”

A

2nd Law of Thermodynamics

60
Q

This law states that regardless of the multiple stages or steps of a reaction, the total enthalpy change for the reaction is the sum of all changes.

A

Hess’ Law

61
Q

The __________ process equation describes expansion and compression processes which include heat transfer.

A

Polytropic

62
Q

He proposed the Carnot Cycle

A

Nicolas Leonard Sadi Carnot

63
Q

type of system that consists of a fixed amount of mass while its volume does not have to be fixed

A

Closed System

64
Q

Equation which relates pressure, volume, and temperature of a gas is called

a. Equation of state
b. Ideal gas eauation
c. Gibbs
d. All of these

A

a. Equation of state

65
Q

The equation PV=nRT is best obeyed by gases at

a. low P, high T
b. high P, low T
c. both low
d. both high

A

a. low P, high T

low P > attractive and repulsive forces become negligible because molecules are spread out

high T > collisions are elastic so KE is preserved

66
Q

Compressibility factor of a gas is

a. not a function of P
b. not a function of its nature
c. not a function of its T
d. unity, if it follows PV=nRT

A

d. Unity

67
Q

Cp - Cv = R is valid for

a. gases at very high P
b. gases at very low T
c. ideal gases
d. all gases

A

c. Ideal gases

68
Q

For monoatomic gases, Cp/Cv equals

A

1.67

69
Q

For an isothermal process, the internal energy of a gas

a. Increases
b. Decreases
c. remains unchanged
d. data is insufficient

A

c. Remains unchanged

70
Q

Cp/Cv for Diatomic is

A

1.4

71
Q

In an adiabatic process

a. heat transfer is zero
b. temperature change is zero
c. work done is a path function
d. enthalpy remains constant

A

a. heat transfer is zero (Q=0)

72
Q

From PV^n=C, when n=0, the process is

a. isochoric
b. isothermal
c. polytropic
d. isobaric

A

d. Isobaric

73
Q

From PV^n=C, the process is isochoric if n equals

A

infinity

74
Q

A solid is transformed into a vapor without gaoing through the liquid phase at

a. below triple point
b. boiling point
c. triple point
d. always

A

a. below triple pt

75
Q

Work output of turbine is ______ the work input to the pump to have profit

a. less than
b. equal to
c. greater than
d. less than or greater than

A

c. greater than

  • so that there will be excess energy that can be sold
76
Q

The efficiency of Carnot cycle is ______ the efficiency of Rankine cycle

a. less than
b. greater than
c. equal to
d. less than or greater than

A

b. greater than

77
Q

Any characteristic of a system is called a __________

A

Property

78
Q

Properties that are independent of the mass of the system

A

Intensive Property

79
Q

Properties that depend on the size or extent of the system

A

Extensive Property

80
Q

Extensive property per unit mass is called _______

A

Specific property

81
Q

Energy can be transferred to or from a system in THREE FORMS:

A
  1. Heat
  2. Work
  3. Mass
82
Q

Cp for Water

A

4.187 KJ/kg•K

1.001 BTU/lbm•F

83
Q

It is a substance that has a fixed chemical composition throughout

A

Pure substance

84
Q

It is the attraction between molecules

A

Intermolecular bonds

85
Q

Intermolecular bonds are strongest in ________ and weakest in gases

a. gases
b. liquids
c. solids
d. solids and liquids

A

c. solids

  • because molecules in solids are closely packed together
86
Q

Triple pt temp of water

A

0.01 C
4.58 mmHg

87
Q

The amount of heat added to effect the phase change is equal to the change in ________

a. U
b. H
c. Q
d. All of the above

A

b. H, Enthalpy

88
Q

It is the change of enthalpy between solid and liquid

A

Latent heat of fusion

89
Q

It is the change of enthalpy between liquid and vapor

A

Latent heat of vaporization

90
Q

It is the change of enthalpy between solid and vapor

A

Latent heat of sublimation

91
Q

At a given pressure, the temperature at which pure substance changes phase is called _______ temperature

A

saturation

92
Q

A ______ process would restoee the system to its INITIAL STATE

A

Reverse

93
Q

_____________ are bodies that can exchange an infinit amount of heat with the system but their temperature never changes

A

Thermal Reservoir

94
Q

What are the THREE types of Thermodynamic Cycles

A
  1. Power Cycle
  2. Refrigeration Cycle
  3. Heat Pump Cycle
95
Q

Devices used to convert HEAT TO WORK (produces work from heat)

A

Heat Engine

96
Q

Heat Engines operate on a _______ cycle

A

Power cycle

-because it produces Work

97
Q

Thermal efficiency is always ______ than unity

A

less

98
Q

Thermal efficiency of ordinary spark ignition engines

A

about 20%

99
Q

Thermal efficiency of diesel engines and large turbine plants

A

about 30%

100
Q

Thermal efficiency of large steam power plants

A

about 40%

101
Q

Fluid which heat is transferred while undergoing a cycle

A

Working fluid

102
Q

Working fluid used in the REFRIGERATION cycle

A

Refrigerant

103
Q

Mostly used working fluid in Heat Engines

A

Water

104
Q

Output for a Heat Engine

A

Work

105
Q

Output of Refrigerators

A

Qc

  • removes heat thus requires a work input
106
Q

It is a reversed Heat Engine

A

Heat Pump

107
Q

Refrigerators and _________ operate on the same cycle but different purpose

a. Heat pump
b. Heat Engine

A

Heat Pump

• Heat Pump - supplies heat to hot reservoir to maintain a heated space
• Refrigerator - removes heat from cold reservoir

108
Q

COP of Heat Pump is always ________ than unity

A

greater

  • because COP of Refrigerator is a positive quantity
109
Q

Heat Pumps today have seasonally averaged COP of ______

A

2-3

110
Q

“It is impossible to devise a cycle such that its only effect is the transfer of heat from a low temp body to a high temp body”

A

Clasius Statement

because a non spontaneous process needs work

111
Q

“It is impossible to build a cycle engine that will have a thermal efficiency of 100%”

A

Kevin Planck

All work can be converted to heat but ALL HEAT CANNOT BE converted to work

112
Q

T or F

A cycle that obeys 1st Law also obeys 2nd Law

A

False

113
Q

What are the TWO Statements of SECOND LAW of Thermodynamics

A
  1. Clausius Statement
  2. Kevin Planck
114
Q

It is a device that violates the laws of thermodynamics

A

Perpetual Motion Machine (PMM)

115
Q

A cyclic process that has the highest efficiency

A

Carnot Cycle

116
Q

When a Carnot cycle is reversed it becomes a ______________

A

Carnot Refrigeration Cycle or a Carnot Heat Pump Cycle

117
Q

Quantitative measure of microscopic disorder for a system

A

Entropy

118
Q

if S total < 0, is the process feasible?

A

not feasible

119
Q

if S total > 0, is the process feasible?

A

feasible but irreversible

120
Q

if S = 0, is the process reversible or irreversible?

A

reversible

121
Q

losses in condenser are _______

small
large
always constant
none

A

small

122
Q

Actual work delivered divided by the corresponding ideal work is known as _______ efficiency

A

turbine

123
Q

Which of the following gives the most work we can get out of an adiabatic system

irreversible compression
irreversible expansion
reversible expansion
reversible compression

A

reversible expansion

124
Q

what happens to delta U when work is done by the system during the adiabatic expansion of ideal gas

zero
decreases
no change
increases

A

decreases

ChELE (21 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions