-
-
-
Heat necessary for phase change
 - L is the latent heat of the phase change
-
-
-
Heat transfer rate
- k is the thermal conductivity, A is cross-sct area, L is length, T is temp. difference between two sides
-
Ideal gas law
- KELVINS
-
-
average kinetic energy of ideal gas
- KELVINS
-
root-mean-square speed
- KELVINS
- M is molar mass (in kg), mu is molecular mass
-
-
Ideal gas at STP
22.4 L at 1 atm and 273 K
-
Zeroth law of thermodynamics
- Transitive property of thermal equilibrium
- Heat flow = 0 in closed systems
-
Work done by ideal gas (heat must be removed)
- Positive when work is done on system, negative when system does work
-
Work when pressure changes
- Area under P-V curve
- Increasing volume gives negative work, decreasing volume gives positive work
-
First law of thermo
- No phase changes.
- For constant volume, W=0 and
-
Isochoric process
- No change in volume
- Change in internal energy due entirely to heat transfer
-
Isothermal process
No temperature changes
-
-
Efficiency of heat engines
- Q_H is heat energy discarded
-
Carnot cycle
1. Isothermal expansion (absorbs heat from high-energy source and expands; because temp doesn't increase, all heat goes into work performed by expanding gas)
2. Adiabatic expansion (system expands w/o exchanging heat w/ surroundings; it thus does negative work, so its internal energy and temperature decrease)
3. Isothermal compression - environment does work on gas, and it discards heat to low-temperature reservoir rather than increasing internal energy
4. Adiabatic compression - system compressed to initial state with no heat exchange, so its internal energy and temp increase
-
Carnot efficiency
- KELVINS
|
|
