Thermodynamics Flashcards
1
Q
Who coined the term “Thermodynamics”?
A
James Prescott Joule
2
Q
Who is considered the Father of Thermodynamics?
A
Nicolas Sadi Carnot
3
Q
Formula for Farenheit to Celcius
A
C = (5/9) (F - 32)
4
Q
Formula for Celcius to Farenheit
A
F = (9/5)C + 32
5
Q
A change in Celcius is ______ths of a change in Farenheit
A
5 / 9
6
Q
Boiling point of Water IN FARENHEIT
A
212 F
7
Q
The unit for temperature named after William Thomson
he is also known as ______________
A
Kelvin, Lord Kelvin :v
8
Q
A change in Celcius is ________ a change in Kelvin
A
Equal to
9
Q
Another absolute temperature scale other than Kelvin
A
Rankine
10
Q
Formula for Rankine
A
R = F + 460
11
Q
A change in Kelvin is ______ths of a change in Rankine
A
5 / 9
12
Q
A change in Rankine is ________ a change in Farenheit
A
Equal to
13
Q
Formula for Thermal Expansion
A
ΔL = α L ΔT
ΔL - change in length
α - Linear coefficient of thermal expansion
L - original Length
ΔT - Change in temperature
14
Q
Linear coefficient of thermal expansion of Copper
A
18 x 10^-6 (in /C)
15
Q
Formula for Areal Expansion
A
ΔA = γ A ΔT
ΔA - change in Area
γ - Areal coefficient of thermal expansion
A - original Area
ΔT - Change in temperature
16
Q
Formula for Volumetric Expansion
A
ΔV) = β V ΔT
ΔV - change in Volume
β - Volumetric coefficient of thermal expansion
V - original Volume
ΔT - Change in temperature
17
Q
Relation of Linear coefficient of thermal expansion(α) to Areal coefficient of thermal expansion(γ) and Volumetric coefficient of thermal expansion(β)
A
β= 3α γ = 2α
18
Q
Defined as the Internal energy in transit from one body to another By virtue of a temperature difference between them
A
Heat
19
Q
1 calorie is equivalent to how many joules?
A
4.186 J
20
Q
1 BTU is equivalent to how many joules?
A
1054 J
21
Q
1 BTU is equivalent to how many foot-pounds?
A
778 ft.lb
22
Q
How much heat in calories is required to heat one gram of water by 1 Celcius?
A
1 Calorie
23
Q
How much heat in BTU is required to heat one pound-mass of water by 1 Farenheit
A
1 BTU
24
Q
A property of a material that defines how many calories or heat is required to raise a material’s Temperature by a specific amount, without considering the material’s mass
A
Heat Capacity
25
Formula of Heat that uses Heat Capacity as a variable
Q = C ΔT (unit in calories)
C-Heat capacity (in cal/Celcius)
Q-Heat in Calories
26
Defined as the Heat Capacity per unit mass
Specific Heat
27
The two variations of Specific Heat Capacity
Cp (Specific Heat @ Constant pressure)
| Cv ( Specific Heat @ Constant Volume)
28
Formula for Molar Specific Heat
Cm = (MW)(c)
MW - Molar Weight
c - Specific Heat
29
Formula of heat, given mass and specific heat
Q = m (c) ΔT
Q - Sensible heat
m - mass of material
c - specific heat of material
30
Specific heat of water
1 cal/(g . C)
31
Specific Heat of Ice
0.5 cal/(g . C)
32
Specific Heat of Steam
0.45 cal/(g . C)
33
The Constant that relates Cp and Cv
Adiabatic Constant (γ)
34
Formula for Adiabatic Constant(γ)
γ = Cp / Cv
35
Adiabatic Constant for a monoatomic compound
γ = 1.67
36
Adiabatic Constant for a diatomic compound
γ= 1.4
37
Latent heat that involves change from solid to liquid and vice versa
Latent Heat of Fusion
38
Latent Heat of Fusion(L) in J/g
L = 333.5 J/g
39
Latent Heat of Fusion(L) in Cal/g
L = 80 Cal/g
40
Latent heat that involves change from Liquid to gas and vice versa
Latent Heat of Vaporization
41
Latent Heat of Vaporization(L) in J/g
L = 2256.7 J/g
42
Latent Heat of Vaporization(L) in cal/g
L = 540 cal/g
43
Latent heat that involves change from Gas to solid and vice versa
Latent Heat of Sublimation
44
Latent Heat of Sublimation(L) in J/g
L = 2838 J/g
45
Latent Heat of Sublimation(L) in cal/g
L = 670 cal/g
46
The heat required to perform phase(solid liquid gas) transformation
Heat of Transformation
47
Formula for Heat of Transformation(Q)
Q = m(L)
m - mass in grams
L - Latent Heat (Fusion, Sublimation, or Vaporization)
48
Formula for the rate of Heat transfer(Q/t)
| AKA FOURIER's LAW
(Q/t) = (k . A . ΔT) / L
k - Thermal Conductivity
A - Cross sectional area (m^2)
ΔT - difference in temperature between the two ends of the material wehre heat is transferred (in Kelvin)
L - Length of material (meters)
49
Formula for Thermal Resistance(R)
R = L / K
k - Thermal Conductivity
L - Length of material (meters)
50
Formula for the Temperature Gradient
Temp. Gradient = ΔT / L
51
The Property that measures the thermal insulating ability of a material
Thermal Resistance
52
Heat transfer that involves the flow of fluids or matter
Convection
53
Formula of Rate of Heat Transfer(Q/t) Due to Convection
Q/t = h . A . ΔT
h - convection Coefficient
A - Area in contact of convection
ΔT - Difference in temperature between two regions
54
Heat transfer that does not require a medium
Radiation
55
Stefan-Boltzmann Constant(sigma)
(sigma) = 5.68 x 10^-8 W / (m^2 . K^4)
56
Formula for Stefan-Boltzmann Law
| AKA HEAT TRANSFER(Q/t) DUE TO RADIATION
Q/t = (sigma)(e)(A) . (T)^4
e = emissivity
A - Area of Coverage
(sigma) - Stefan-Boltzmann Constant
T - Temperature; if Temp. difference exists, replace T^4 with: (T2)^4 - (T1)^4
57
The ability to emit radiation
emissivity
58
emissivity(e) of the sun
1
59
emissivity(e) of a perfect reflector
0
60
emissivity(e) of a black body
1 Manacup..... jk lang,
Answer: 1
61
The formula that depicts the first law of thermodynamics
U = +-(Q) +-(W)
U - CHANGE in internal energy of system
Q - Heat absorbed/released by system
W - Work done on/by the system
62
Who coined the term "Energy"
Thomas Young
63
In Engineering convention, If heat is ABSORBED by the system, Q is (Positive/Negative)?
Positive
64
In Engineering convention, If heat is RELEASED by the system, Q is (Positive/Negative)?
Negative
65
In Engineering convention, If work is done ON the system, W is (Positive/Negative)?
Positive
66
In Engineering convention, If work is done BY the system, W is (Positive/Negative)?
Negative
67
The Interface that separates a system to its surroundings
Boundary
68
A system where matter enters and leaves at the same rate
Steady Flow System
69
A system where NOTHING crosses the boundary
Isolated System
70
A system where heat does not cross the boundary
| Therefore ΔQ = 0
Adiabatic System
71
A system where heat MAY cross the boundary
Diathermic System
72
A system where Matter may not cross the boundary, but heat may cross
Closed System
73
Another term for Closed System
Control Mass System
74
A system where EVERYTHING can cross the Boundary
Open System
75
Another Term for Open System
Control Volume System
76
The fastest reaction in a Thermodynamic system
Adiabatic
77
In an adiabatic system, only ___________ contributes to a change in the internal energy of the system
work
78
Value of Cv of a monoatomic substance
Cv = 3R / 2
R - 8.314 J/k.mol
79
Value of Cp of a monoatomic substance
Cp = 5R/2
R - 8.314 J/k.mol
80
Value of Cv of a diatomic substance
Cv = 5R/2
R - 8.314 J/k.mol
81
Value of Cp of a diatomic substance
Cp = 7R/2
R - 8.314 J/k.mol
82
Formula that depicts relationship of Cv to Cp
Cp = Cv + R
R - 8.314 J/k.mol
83
Formula for Heat in an adiabatic process
Q = n(Cp OR Cv) . ΔT
n - number of moles
ΔT - Change in Temperature
84
Formula for Work in an adiabatic process
W = (1 / (γ - 1))[P2V2 - P1V1]
γ - adiabatic constant
85
Thermodynamic process where pressure is held constant
Isobaric
86
Thermodynamic process where Volume is held constant
Isochoric
87
Thermodynamic process where Temperature is held constant
Isothermal
88
Formula for Work in an Isobaric Process
W = -P . ΔV
P - Pressure
V - Volume
89
Formula for Heat in an Isobaric Process
Q = m Cp ΔT
m - mass
Cp - Specific heat when constant pressure
ΔT - Change in Temperature
90
In an Isothermal process, the energy in a system __________?
Remains the same (Change in energy is zero)
91
In an Isothermal process, What two properties of a system are the same in magnitude?
Heat and Work:
U = Q + W ; but in isothermal, U = 0
therefore, Q = -W
92
Formula for Work in an Isothermal process (Using Initial and Final Volume)
W = -nRT ln (V2 / V1)
n - # moles
R -8.314 J/k.mol
T - Temp. in Kelvin
93
Formula for Work in an Isothermal process (Using Initial and Final Pressure)
W = +nRT ln (P2 / P1)
n - # moles
R -8.314 J/k.mol
T - Temp. in Kelvin
94
The work in an Isochoric Process is equal to
since ΔV = 0,
W = -P . ΔV
W = 0
95
Change in internal energy is attributed only to ________ in an isochoric process
Answer: Heat
ΔU = Q + W
but W = 0
therefore, ΔU = Q
96
Formula for Heat in an Isochoric Process
Q = m Cv ΔT
m - mass
Cv - Specific heat when constant volume
ΔT - Change in Temperature
97
An adiabatic process in which there is no change in entropy (ΔS = 0)
Isentropic Process
98
An adiabatic Process that Throttles
Isenthalpic Process
99
The Change in Enthalphy in an Isenthalpic Process is ____________________
ΔH = 0
100
With Throttling, there is a significant drop in _________
Pressure
| P2 < P1
101
When Gas is Throttled, the change in temperature over the change in pressure is called
Joule -Thomson Coefficient
102
All Thermodynamic processes are (Reversible/Irreversible)
Irreversible
103
Formula for Polytropic Process
P1 . (V1)^n = P2 . (V2)^n
n - Polytropic Exponent
104
If the Polytropic Exponent(n) is ZERO, the effect is that the process becomes a/an ___________ process
Isobaric
105
If the Polytropic Exponent(n) is ONE, the effect is that the process becomes a/an ___________ process
Isothermal
106
If the Polytropic Exponent(n) is INFINITY, the effect is that the process becomes a/an ___________ process
Isochoric
107
If the Polytropic Exponent(n) is the ADIABATIC CONSTANT, the effect is that the process becomes a/an ___________ process
Adiabatic
108
If the Polytropic Exponent(n) is K, the effect is that the process becomes a/an ___________ process
Isentropic
Note: idk what K is :v, maybe boltzmann
109
Formula for Polytropic Specific Heat
Cn = Cv . ( n - K ) / ( n - 1 )
n - polytropic exponent
Note: idk what K is :v, maybe boltzmann
110
2nd Law of Entropy
Entropy Increases as time approaches Infinity.
| Entropy never increases
111
3rd Law of Entropy
Entropy is 0 at T = 0 Kelvin
112
0th Law of Entropy
if Ta = Tb, and Ta = Tc,
| therefore, Tb = Tc
113
What is the Input and Output of a Heat Engine?
Input: Qhot
Output: Work(out)
114
Formula for Output Work in a Heat Engine
Wout = Qh - Qc
115
Formula for Heat Engine Efficiency(e)
Derivation:
e = Output / Input
e = Wout / Qh
e = (Qh - Qc) / Qh
Final Ans: e = 1 - (Qc / Qh)
116
Formula for Heat Engine CARNOT EFFICIENCY
e = 1 - (Tc / Th)
| IN KELVIN
117
Formula for Refrigerator CARNOT Coefficient of Performance
COP = (Th - Tc) / Tc
| IN KELVIN
118
What is the Input and Output of a Refrigerator?
Input: Work(in)
Output: Qcold
119
Formula for Output Qc in a Refrigerator
Qc = Qh - Win
120
Formula for the Coefficient of Performance of a Refrigerator
Derivation:
COP = Output / Input
COP = Qc / Win
Final Ans: COP = Qc / (Qh - Qc)
121
What is the Input and Output of a Heat Pump?
Input: Work(in)
Output: Qhot
122
Formula for Input Work in a Heat Pump
Win = Qh - Qc
123
Formula for Coefficient of Performance of a Heat Pump
Derivation:
COP = Output / Input
COP = Qh / Win
Final Ans: COP = Qh / (Qh - Qc)
124
Another parameter that measures refrigerator performance
Energy Efficiency Ratio (EER)
125
Formulas for Energy Efficiency Ratio(EER)
```
EER = (Q per Hour)/Power
EER = 3.42 . COP
```
Q - MUST BE IN BTU/hour
126
Kevin-Planck Statement
Assume a Heat Engine:
Because Qc can never become 0,
from the formula Wout = Qh - Qc,
Conclusion: Wout can never be equal to Qh
127
Clausius Statement
Assume a Refrigerator/Air conditioner:
Because the input work(Win) required to cool a system cannot be just 0,
from the formula Qc = Qh - Win,
Conclusion: Qc cannot equal Qh
Restatement: "Heat does not flow from cold to hot normally"
128
Caratheodory Statement
At equilibrium, There are equilibrium states inaccessible by an adiabatic process
129
Nernst Postulate
from the 3rd Law if Thermodynamics (Tk = 0 Kelvin, The entropy is zero), "It is impossible to achieve this state with finite number of operations"
130
The amount of Disorder in a system
entropy
131
The formula for the Change in Entropy
ΔS = Q / T
Q - Heat
T -Temperature
132
When Solid transfoms Into Liquid and/or Liquid into Gas(S>>>>L>>>>G), Change in Entropy (Increases/Decreases)
Increases
133
When Gas transfoms Into Liquid and/or Liquid into Solid(G>>>>L>>>>S), Change in Entropy (Increases/Decreases)
Decreases
134
What are the processes involved in a Carnot Cycle
Involves 2 Adiabatic and 2 Isothermal Processes to complete one cycle (4 processes in total)
135
The Phase transformation from Gas to Solid
Deposition
136
The Triple Point of Water is Found at what temperature?
0.01 Celcius
137
Water is most dense at what temperature?
4 Celcius
138
How much of a Proton's Energy is attributed to Heat?
1/3 of Proton's energy is equal to heat
139
Unit of electron volts (eV)
Joules per Coloumb (J/C)
140
If in problems a gas is not specified if whether monoatomic or diatomic, what do we assume by default?
the gas is monoatomic
141
Kinetic Energy of MONOATOMIC gas
KE = 3.K.T / 2
k - boltzmann constant
T - Temp. in Kelvin
142
Kinetic Energy of DIATOMIC gas
KE = 5.K.T / 2
k - boltzmann constant
T - Temp. in Kelvin
143
Vrms of MONOATOMIC gas (given Temperature and mass)
Vrms = sqrt( (3KT / m)
k - boltzmann constant
T - Temp. in Kelvin
m - mass in kg
144
Vrms of DIATOMIC gas (given Temperature and mass)
Vrms = sqrt( (5KT / m)
k - boltzmann constant
T - Temp. in Kelvin
m - mass in kg
145
Vrms of MONOATOMIC gas (given Temperature and Molar mass)
Vrms = sqrt( (3RT / MM)
R - 8.314 J/K.mol
T - Temp. in Kelvin
MM - Molar Mass
146
Vrms of DIATOMIC gas (given Temperature and Molar mass)
Vrms = sqrt( (5RT / MM)
R - 8.314 J/K.mol
T - Temp. in Kelvin
MM - Molar Mass
