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Chapter 14
- Thermodynamics:
  - Thermodynamics focuses on energy rather than forces.
    - Conservation of energy is a key pillar of thermodynamics.
      - Quantities such as temperature and heat are needed for properties of system interactions.
        A system contains multiple particles, usually a very large amount.
        Systems are able to exchange energy with other systems.
        A balloon filled with oxygen is an example of a system.
        In comparing tow systems, they may not be identical on the molecular level.
        Various properties of the system as a whole will be the same
        System wide properties include temperature and pressure.
        We are generally interested in the macroscopic properties of the system.
        They describe the behavior of the system o a scale much larger than the individual particles.
        Macroscopic and microscopic properties of the system are connected.
- Temperature:
  - Temperature is not contained in nor derivable from Newton's laws.
    - Heat flows from hot to cold.
      - Thot > Tcold
      - Temperature is connected with the terms "hotness" or "coldness".
        Eventually two interacting systems will have the same temperature.
        They will reach a thermal equilibrium.
        The energy that flows between the systems is called heat or heat energy.
        Heat is energy that passes from one system to another by virtue of a temperature difference.
        Heat = Energy
        According to the principle of conservation of energy the heat energy that leaves system 1 must equal the amount that enters system 2.
        The direction of the transfer depends only on the temperature difference.
        UNITS OF HEAT:
        SI unit of heat is the same as energy. Joule (J).
        A unit called the calorie is widely used for heat. 1 cal = 4.186 J
        Calorie with uppercase C is used in food. 1 Calorie = 1000 calories.
        Three temperature scales that are common today:
        Celcius
        Water freezes at 0 degrees.
        Water boils at 100 degrees.
        Fahrenheit
        Water freezes at 32 degrees.
        Water boils at 212 degrees.
        Kelvin
        Water freezes at 273.15 K
        Water boils at 373.15 K
        No degree symbol is used.
        Temperature Conversions:
        TK = TC + 273.15
        Tf = 9/5Tc + 32
        0th Law.
Chapter 15
- Gases and Kinetic Theory
  - Newton's Laws are used to analyze the behaviors of gas
  - Dilute gases can lead to connections between temperature and motion on an atomic scale
  - Ideal gas notion "kinetic theory"
    - Apply to dilute gases
  - Atomic mass (M) in (g) is the mass of one atom. m=M/N
    - N= Avogadro's number
  - Gases
    - Collide with other gas molecules and walls of their container
    - Molecules are in constant motion
    - Molecules move in all directions and with different speeds
  - Avagadro's Number: N= 6.02 x 10^23
    - Connects microscopic world to macroscopic world
    - Number of particles in 1 mole
  - Avogadro's Law
    - Gas at a constant pressure and temperature. Volume is proportional to the number of molecules in sample
      - V proportional to N
  - Charle's Law
    - Gas at constant pressure. If temperature changes slightly the volume changes by a small amount
    - V is proportional to T
  - Boyle's Law
    - Gas at constant temperature. Product of pressure and volume is constant.
    - PV= constant
    - P proportional to 1/V
  - Gay-Lussac's Law
    - Gas held in container with constant volume, changes in pressure are proportional to changes in temperature
      - P proportional T
    - Involved with gas thermometers
  - Ideal Gas Law
    - PV= nRT
    - R= 8.31 J/mole K
    - n= # of moles of gas present
    - Ideal Gas Law represented with number of particles. PV=(N/Na)RT= N(R/Na) T
      - R/Na is Boltzmann's Constant (kB)
        kB=1.38x10^23
    - PV= N kB T
  - Elastic Collisions: The speed before and after will be the same.
    - P=Nmv^2/3V and PV=N (mv^2/3)
  - Kinetic Energy: 3/2 kB T
  - Molecular Speeds: v=sqrt of 3 kB T/m
  - Specific Heat of Ideal Gas
    - Heat energy added to ideal gas will cause increase in both KE and internal energy (U)
- Internal Energy: Mechanical energy of a particle in an ideal gas is equal to its KE
  - Internal Energy depends only on the number of particles present and the temperature of the gas
  - In terms of the number of moles: U=3/2 n R T
  - Applies to monatomic gases
  - change U= change Q= 3/2 n Kb change in T
Chapter 16
- The principles of thermodynamics are enshrined in 4 laws. Three are discussed
  - The Zeroth Law of Thermodynamics concerns the flow of heat
    - If System A and B are ine equilibrium with system C, then A and B are in equilibrium with each other
  - The First Law states that the change in internal energy of a system is equal to the heat flow Q into the system minus the work W done by the system on its environment
    - Change in U = Q - W
      - Work = P(Change in V) = 0 in an isochoric process
      - W = n RT ln(V(f)/V(i) in an isothermal process
      - W = P(Change in V) in an isobaric process
      - W = The area under the PV diagram in an adiabatic process
        This is demonstrated on the graph below
    - Work is positive when a gas expands, and force is parallel to displacement; it is negative when a gas compresses, and force is anti-parallel to displacement.
    - U = (3/2) N x K(B) x T or (3/2) n R T
  - The Second Law states in simple terms that heat flows from a hot object to a colder one.
    - The Second Law also describes irreversible processes
      - In two reservoirs of different temperature, Q(c)/Q(h) = T(c)/T(h)
        Efficiency = 1 - (T(c)/T(h)). This is the maximum efficiency of a heat engine.

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