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Thermodynamics, Dimension, Definition of Energy Balance: The net change in…

- - - - The work done on adiabatic system = increase in the energy of system
    - - Sufficiently slow process that allows the
        system to adjust to itself internally so that properties in one part of the system do not
        change any faster than those at other parts.
- - - - Closed system or also known as control mass is for energy transfer
      - Open system or also known as control volume is for mass and energy transfer
      - Isolated system is a system without energy or mass transfer across boundary
    - - Extensive
        
        Those whose values depend on the size or the extent of the system
      - Intensive
        
        Those that are independent of the mass of a system
  - - - Work (W=Fs)
        
        Mechanical Form
        
        Shaft Work
        
        Spring Work
        
        Non-mechanical Form
        
        Electric Work
        
        Magnetic Work
        
        Electrical Polarization Work
      - Heat
        
        The form of energy that is transferred between two systems or system and its surroundings by virtue of a temperature difference
        
        Presence of heat
        
        Mechanism of heat transfer
        
        Convection
        
        Transfer of energy between a solid surface and the adjacent fluid that is in motion, and it involves the combined effects of conduction and fluid motion.
        
        1 more item...
        
        Radiation
        
        Transfer of energy due to the emission of electromagnetic waves or photons
        
        1 more item...
        
        Conduction
        
        Transfer of energy from the more energetic particles of substance to the adjacent less energetic ones as a result of interaction between particles.
        
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        Absence of heat
        
        Adiabatic process
        
        System is well insulated. Both system and surroundings are at the same temperature
  - - - Saturation Temperature, Tsp
        
        The pressure at which a pure substance changes phase at a given temperature
    - - Saturation Pressure, Tsa
        
        The temperature at which a pure substance changes phase at a given pressure
      - Pascal's Law
      - Device for pressure measurement
        
        Bourdon tube
        
        Piezoelectric Transducer
- - - - Enthalpy, h is the sum of the internal energy added to the product of the pressure and volume of the system
        
        Enthalpy of vaporization (Latent heat of vaporization)
- - - - What are the form of the energy?
        
        Kinetic energy
        
        Potential energy
  - - - What are the form of the energy?
        
        Kinetic energy
      - forms of energies that can make up sensible energy
        
        E.g. Molecular translation, molecular rotation, electron translation,
        molecular vibration, electron spin, nuclear spin
- - - - Latent heat
        
        The amount of energy absorbed or released during a phase-change process
      - Latent heat of vaporization
        
        The amount of energy absorbed during vaporization and it is equivalent to the energy released during condensation.
      - Latent heat of fusion
        
        The amount of energy absorbed during melting. It is equivalent to the amount of energy released during freezing
    - - P-V Diagram
        
        Extending to include the solid phase
        
        Saturated liquid and saturated vapor states of
        water on T-v and P-v diagrams.
      - T-v diagram of constant-pressure phase change processes of a pure substance at various pressures
        
        The saturation line will shrink as the pressure increase and it reaches critical point.
        
        The saturated liquid states can be connected by a line called the saturated liquid line and vapor states in the same figure can be connected by another line, called the saturated vapor line. When this two line meets at critical point, it will form a dome.
      - P-T Diagram
        
        The sublimation line separates the solid and vapor regions, the vaporization line separates the liquid and vapor regions, and the
        melting (or fusion) line separates the solid and liquid regions. These three
        lines meet at the triple point, where all three phases coexist in equilibrium. The vaporization line ends at the critical point because no distinction can be
        made between liquid and vapor phases above the critical point.
      - P-V-T Surface
        
        Ideal Gas
        
        Equation of state: Any equation that relates the pressure, temperature, and specific
        volume of a substance.
        
        The ideal gas equation of state is used when the pressure is small compared to the critical pressure.
        
        When the temperature is twice the critical temperature and the pressure is less than ten
        times the critical pressure
        
        At high temperatures (TR > 2), ideal-gas behavior can be assumed with
        good accuracy regardless of pressure (except when PR >> 1)
        
        The deviation of a gas from ideal-gas behavior
        is greatest in the vicinity of the critical point.
        
        At very low pressures (PR << 1), gases behave as ideal gases regardless
        of temperature
    - - Saturated Vapor
        
        A vapor that is about to condense
      - Superheated Vapor
        
        A vapor that is not about to condense
    - - Compressed Liquid (Subcooled Liquid)
        
        Water exists in the liquid phases and it is not to vaporize
      - Saturated Liquid
        
        A liquid that is about to vaporize
- - - - Net transfer of a quantity is equal to the difference between the amounts transferred in and out, thus energy balance can be written as below: