Proven Mnemonics & Acronyms β fast to learn, hard to forget.
0 correct0 wrong? remaining
questions correct
π₯ How Flashcards Work
A quick walkthrough of tap-to-flip, rating, and how card colors track what you're struggling with.
← BackNext →
Thermodynamics deck1 of 15
Tap to flip
←→
How well do YOU think you know this?
EasyMediumHardHarder
Tap to flip back
Thermodynamics deck
Easy0
Medium0
Hard0
Harder0
Ideal Gas Law
PV = nRT
Ideal Gas Law
Pressure Γ Volume = moles Γ gas constant Γ Temperature
P = pressure, V = volume, n = moles, R = 8.314 J/molΒ·K, T = temperature in Kelvin. Compress gas β pressure rises. Heat gas β pressure or volume increases.
This lesson's animated video hasn't been made yet β check back soon.
Flashcard
π Ideal Gas Law
The ideal gas law?
Tap to flip
π Answer
PV = nRT
P = pressure, V = volume, n = moles, R = 8.314 J/molΒ·K, T = temperature in Kelvin. Compress gas β pressure rises. Heat gas β pressure or volume increases.
Tap to flip back
Heat Transfer
CCR: Conduction, Convection, Radiation β 3 heat transfer modes
Heat Transfer
Three ways heat moves β remember CCR
Conduction: direct contact (metal spoon in soup). Convection: fluid movement (boiling water). Radiation: electromagnetic waves (sun warming you). Radiation needs no medium.
This lesson's animated video hasn't been made yet β check back soon.
Flashcard
π Heat Transfer
CCR β the three modes of heat transfer?
Tap to flip
π Answer
CCR: Conduction, Convection, Radiation β 3 heat transfer modes
CConduction β contact
CConvection β fluid movement
RRadiation β EM waves, no medium needed
Tap to flip back
Second Law
Entropy always increases in isolated systems β disorder grows
Second Law
Things move from order to disorder spontaneously β never the reverse
A shattered egg never reassembles. Ice melts in warm room but water won't freeze spontaneously. The universe trends toward maximum disorder (maximum entropy).
This lesson's animated video hasn't been made yet β check back soon.
Flashcard
π Second Law
The second law of thermodynamics?
Tap to flip
π Answer
Entropy always increases in isolated systems β disorder grows
A shattered egg never reassembles. Ice melts in warm room but water won't freeze spontaneously. The universe trends toward maximum disorder (maximum entropy).
Tap to flip back
Carnot Efficiency
Carnot efficiency = 1 - (Tc/Th) β maximum possible efficiency of any heat engine
Carnot Efficiency
No real engine can exceed Carnot efficiency β it's the theoretical maximum
Efficiency depends only on the temperatures of the hot (Th) and cold (Tc) reservoirs in Kelvin. Higher temperature difference β higher efficiency. Real engines always fall short due to irreversibility.
This lesson's animated video hasn't been made yet β check back soon.
Flashcard
π Carnot Efficiency
Carnot efficiency β the formula?
Tap to flip
π Answer
Carnot efficiency = 1 - (Tc/Th) β maximum possible efficiency of any heat engine
Efficiency depends only on the temperatures of the hot (Th) and cold (Tc) reservoirs in Kelvin. Higher temperature difference β higher efficiency. Real engines always fall short due to irreversibility.
Tap to flip back
Temperature Scales
Temperature scales: K = Β°C + 273. Absolute zero = 0 K = -273Β°C β molecules have the minimum possible energy.
Temperature Scales
Converting between Celsius and Kelvin β and what absolute zero means
Always use Kelvin in gas law calculations. 0 K (absolute zero): minimum possible temperature, molecules have minimum kinetic energy. Room temperature β 293 K. Water freezes at 273 K, boils at 373 K. Fahrenheit: Β°F = (9/5)Β°C + 32.
This lesson's animated video hasn't been made yet β check back soon.
Flashcard
π Temperature Scales
Kelvin vs Celsius β conversion and absolute zero?
Tap to flip
π Answer
Temperature scales: K = Β°C + 273. Absolute zero = 0 K = -273Β°C β molecules have the minimum possible energy.
Always use Kelvin in gas law calculations. 0 K (absolute zero): minimum possible temperature, molecules have minimum kinetic energy. Room temperature β 293 K. Water freezes at 273 K, boils at 373 K. Fahrenheit: Β°F = (9/5)Β°C + 32.
Tap to flip back
Specific Heat Capacity
Specific heat capacity: Q = mcΞT. Water has high specific heat β resists temperature change.
Specific Heat Capacity
How much energy is needed to change a substance's temperature
Q = heat energy (J), m = mass (kg), c = specific heat capacity (J/kgΒ·K), ΞT = temperature change. Water: c = 4,186 J/kgΒ·K β very high. Metals: much lower c. High specific heat = more energy needed to heat up = slower temperature change. This is why coastal cities have milder climates.
This lesson's animated video hasn't been made yet β check back soon.
Flashcard
π Specific Heat Capacity
Specific heat capacity β formula, and why water?
Tap to flip
π Answer
Specific heat capacity: Q = mcΞT. Water has high specific heat β resists temperature change.
Q = heat energy (J), m = mass (kg), c = specific heat capacity (J/kgΒ·K), ΞT = temperature change. Water: c = 4,186 J/kgΒ·K β very high. Metals: much lower c. High specific heat = more energy needed to heat up = slower temperature change. This is why coastal cities have milder climates.
Tap to flip back
Thermal Expansion
Thermal expansion: solids, liquids, and gases all expand when heated. Bridges have expansion joints.
Thermal Expansion
Most materials expand when heated and contract when cooled
Linear expansion: ΞL = Ξ±LΞT where Ξ± = coefficient of linear expansion. Volume expansion: ΞV = Ξ²VΞT where Ξ² β 3Ξ±. Applications: gaps in railroad tracks and bridges (expansion joints), thermostats (bimetallic strips), thermometers. Exception: water expands when it freezes (ice less dense than water).
This lesson's animated video hasn't been made yet β check back soon.
Flashcard
π Thermal Expansion
Thermal expansion?
Tap to flip
π Answer
Thermal expansion: solids, liquids, and gases all expand when heated. Bridges have expansion joints.
Linear expansion: ΞL = Ξ±LΞT where Ξ± = coefficient of linear expansion. Volume expansion: ΞV = Ξ²VΞT where Ξ² β 3Ξ±. Applications: gaps in railroad tracks and bridges (expansion joints), thermostats (bimetallic strips), thermometers. Exception: water expands when it freezes (ice less dense than water).
Tap to flip back
Heat Engines
Heat engines: take heat from hot reservoir, do work, dump waste heat to cold reservoir
Heat Engines
How all heat engines work β from car engines to power plants
All heat engines follow the same principle: absorb heat Qh from hot source, convert some to work W, reject remaining heat Qc to cold sink. Efficiency = W/Qh = 1 - Qc/Qh. Carnot efficiency is the theoretical maximum: 1 - Tc/Th. Real engines always less efficient due to friction and irreversibility.
This lesson's animated video hasn't been made yet β check back soon.
Flashcard
π Heat Engines
How does a heat engine work?
Tap to flip
π Answer
Heat engines: take heat from hot reservoir, do work, dump waste heat to cold reservoir
All heat engines follow the same principle: absorb heat Qh from hot source, convert some to work W, reject remaining heat Qc to cold sink. Efficiency = W/Qh = 1 - Qc/Qh. Carnot efficiency is the theoretical maximum: 1 - Tc/Th. Real engines always less efficient due to friction and irreversibility.
Tap to flip back
Phase Changes
Phase changes: melting, freezing, vaporization, condensation, sublimation. Temperature constant during phase change.
Phase Changes
What happens to temperature during a change of state
During a phase change, temperature stays constant while energy goes into breaking/forming intermolecular bonds. Latent heat of fusion (melting/freezing): energy to change between solid and liquid. Latent heat of vaporization: energy to change between liquid and gas. Q = mL where L = latent heat.
This lesson's animated video hasn't been made yet β check back soon.
Flashcard
π Phase Changes
Phase changes β what happens to temperature?
Tap to flip
π Answer
Phase changes: melting, freezing, vaporization, condensation, sublimation. Temperature constant during phase change.
During a phase change, temperature stays constant while energy goes into breaking/forming intermolecular bonds. Latent heat of fusion (melting/freezing): energy to change between solid and liquid. Latent heat of vaporization: energy to change between liquid and gas. Q = mL where L = latent heat.
Tap to flip back
Zeroth Law
Zeroth Law of Thermodynamics: if A=B in temperature and B=C, then A=C. Basis of thermometers.
Zeroth Law
The law that makes temperature measurement possible
If object A is in thermal equilibrium with object B, and object B is in thermal equilibrium with object C, then A and C are in thermal equilibrium with each other. This is why thermometers work β they reach equilibrium with whatever they measure. Called 'zeroth' because it was defined after 1st and 2nd laws.
This lesson's animated video hasn't been made yet β check back soon.
Flashcard
π Zeroth Law
The Zeroth Law of Thermodynamics?
Tap to flip
π Answer
Zeroth Law of Thermodynamics: if A=B in temperature and B=C, then A=C. Basis of thermometers.
If object A is in thermal equilibrium with object B, and object B is in thermal equilibrium with object C, then A and C are in thermal equilibrium with each other. This is why thermometers work β they reach equilibrium with whatever they measure. Called 'zeroth' because it was defined after 1st and 2nd laws.
Q/t = kAΞT/d. k = thermal conductivity (high k = good conductor, low k = good insulator). A = cross-sectional area. ΞT = temperature difference. d = thickness. Metals have high k. Air, wood, foam have low k. R-value (insulation): R = d/k, higher R = better insulator.
Q/t = kAΞT/d. k = thermal conductivity (high k = good conductor, low k = good insulator). A = cross-sectional area. ΞT = temperature difference. d = thickness. Metals have high k. Air, wood, foam have low k. R-value (insulation): R = d/k, higher R = better insulator.
Tap to flip back
Four Laws of Thermodynamics
ZFST β Zeroth (equilibrium), First (energy conservation), Second (entropy), Third (absolute zero)
All four laws of thermodynamics and what each governs
You can remember them as: you must play, you cannot win, you cannot break even, you cannot quit
Zeroth Law: if A is in thermal equilibrium with B and B with C, then A is in equilibrium with C β defines temperature. First Law: ΞU = Q β W β energy is conserved (heat added minus work done by system). Second Law: entropy of isolated system never decreases β heat flows hot to cold, not reverse. Third Law: as Tβ0 K, entropyβ0 (perfect crystal at absolute zero). Mnemonic for 1st and 2nd: you can't win (can't create energy), you can't break even (can't avoid entropy increase).
Zeroth
Thermal equilibrium is transitive β defines temperature measurement
First
ΞU = Q β W β energy conserved, just changes form
Second
Entropy never decreases β irreversibility of natural processes
This lesson's animated video hasn't been made yet β check back soon.
Flashcard
π Four Laws of Thermodynamics
ZFST β the four laws of thermodynamics?
Tap to flip
π Answer
ZFST β Zeroth (equilibrium), First (energy conservation), Second (entropy), Third (absolute zero)
ZerothThermal equilibrium is transitive β defines temperature measurement
FirstΞU = Q β W β energy conserved, just changes form
SecondEntropy never decreases β irreversibility of natural processes
Tap to flip back
Entropy and Disorder
S = k ln W β entropy is the number of microstates. More disorder = higher entropy = more probable state.
What entropy actually measures and why it always increases
The universe tends toward higher entropy because there are vastly more disordered states than ordered ones
Boltzmann entropy: S = k_B ln W where W = number of microstates consistent with the macrostate. k_B = 1.38Γ10β»Β²Β³ J/K. A gas spreading to fill a room: overwhelming number of microstates with gas spread out vs. concentrated β statistically certain to spread. Entropy change: ΞS = Q/T for reversible process. ΞS > 0 for irreversible. Gibbs free energy: G = H β TS. Spontaneous when ΞG < 0. High T favors entropy-driven reactions. Low T favors enthalpy-driven.
S = k ln W
Entropy = Boltzmann constant Γ ln(number of microstates)
ΞS = Q/T
Entropy change for reversible process β larger at lower T
IsothermalT constant β ΞU = 0 β Q = W for ideal gas
AdiabaticQ = 0 β ΞU = βW β temperature changes as work done
IsochoricV constant β W = 0 β all heat goes to internal energy
Tap to flip back
Heat Engines and Refrigerators
Engine: takes heat from hot, does work, dumps heat to cold. Refrigerator: reverse β work in, moves heat from cold to hot.
How heat engines and refrigerators work as thermodynamic cycles
COP of refrigerator = Q_cold / W. COP of heat pump = Q_hot / W. Both limited by Carnot.
Heat engine: Q_H (from hot source) β W (work out) + Q_C (to cold sink). Efficiency Ξ· = W/Q_H = 1 β Q_C/Q_H β€ 1 β T_C/T_H (Carnot limit). Refrigerator: W (work in) moves Q_C from cold reservoir, dumps Q_H = Q_C + W to hot. COP_refrig = Q_C/W = T_C/(T_HβT_C) at Carnot. Heat pump: same as refrigerator but goal is heating. COP_HP = Q_H/W = T_H/(T_HβT_C). Heat pumps can be more than 100% efficient (move more heat than work input) β they move existing heat, not create it.