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Thermodynamics - Coggle Diagram

- - - - High density
      - Cannot flow
      - Volume is fixed
      - Cannot be easily compressed
      - Fixed shape
      - Regular pattern of particles, closely packed together and held in place by strong, attractive forces. Particles can vibrate around fixed positions
    - - High density
      - Flows
      - Fixed volume
      - Cannot be easily compressed
      - Takes the shape of the bottom of the container it is in
      - Particles are arranged irregularly and can move past each other. Particles are not in a fixed position how they still have weak bonds connecting them and are still very close together.
    - - Low density
      - Flows very quickly
      - Volume varies
      - Can be compressed easily
      - Spreads rapidly and fills container
      - Have an irregular arrangement and move randomly in all directions. Particles are very far apart
      - Pressure in gases
        
        pressure = force/area
        
        The pressure of gas inside a container is caused by huge numbers of tiny collisions happening between the gas particles and the walls of the container.
        
        Increasing temperature increases the kinetic energy of the particles, meaning they move faster and have more frequent collisions with the sides of the container, increasing pressure
  - - - Random motion of particles due to hundreds of collisions between particles and even smaller air/water particles
  - - - Surface Area
        
        Increasing surface are increases the number of particles near the surface and increases the rate of evaporation
      - Temperature
        
        Increasing temperature increases the average speed of particles in the liquid. As more particles are moving fast enough to escape, the rate of evaporation increases
      - Air flow
        
        When evaporation takes place, the escaped particles can form a vapor above the surface of the liquid which slows down the rate of evaporation
        
        Increasing air flow above the surface will clear away water vapor and increase rate of evaporation
  - - - Increasing temperature increases the kinetic energy of the particles, meaning they move faster and have more frequent collisions with the sides of the container, increasing pressure
    - - Decreasing the volume of a container will decreases the distance the gas particles have to travel between collisions with the walls. This means there will be a larger number of collisions between the gas particles and the container
      - pressure x volume = constant
        
        only applies if temperature of gas is kept constant
- - - - Lattice Vibration
        
        The higher the temperature of a solid, the greater the vibration of the particles and this increase in vibrations affects other nearby atoms and causes them to vibrate
        
        Fairly slow
      - Metals are more rapid conductors as they have free electrons. These electrons are not fixed in place and can move quickly from one end of the material to the other.
        
        When part of the metal is heated, the electrons in this area quickly spread out along the metal. As they travel, they collide with the atoms and cause increased vibration, raising the temperature.
    - - Plastic and Glass
      - Reduce energy transfer
      - A material that does not allow the free movement of charges
  - - - Surface color
        
        Silvered surfaces
        
        Poor absorbers of radiation, reflect instead
        
        Poor emitter of radiation, cools slower
        
        Black surfaces
        
        Good absorbers of radiaition
        
        Good emitters of radiation
        
        Leslie cube can be used to show this
      - Surface texture
        
        A shiny surface is smooth and increases reflectiveness, so is not good at absorbing radiation or emitting radiation
        
        Rougher surfaces are good absorbers of radiation and better emitters
      - Surface temperature
        
        The hotter an object is, the more infrared radiation it emits
      - Surface area
        
        A bigger object emits more radiation than a smaller object at the same temperature
  - - - Double layer of glass and vacuum between layers.
        
        Vacuum contains no particles and so there can be no convection or conduction from one layer to another
        
        Glass is also an excellent insulator so there is very little conduction
    - - Cavity walls (Full or air and are bad conductors)
      - Cavity wall insulation (Foam inside wall has loads of air pockets that stop convection currents from forming)
      - Curtains (Stop convection currents from forming and are opaque so red infrared loss)
      - Draught excluders (Plastic Strips around doors and windows stop hot air from escaping)
      - Silver layer behind radiators(radiators next to walls heat the walls, which wastes energy . Placing a shiny silver card behind radiator reflects the infrared radiation)
      - Loft insulation (Insulation (normally made of fibre glass) traps the hot air that rises in air pockets)
      - Double glazing (Traps air between pains of glass. Can be improved further by sucking out air between pains and creating a vacuum)
- - - - In a solid , they will stay in the same relative position but will move slightly further apart
      - In liquids and gases, the particles will move faster and more freely
        
        Liquids will expand more than solids
        
        Gas will continue to expand if kept at a constant pressure. If gas is held within a container, the gas can't expand and so the pressure will increase
  - - - m is mass of object and c is specific heat capacity
    - - Amount of energy stored per kilogram of the material per degree Celsius
      - unit J/kg℃
      - change in energy = mc△T
        
        m is mass in kg, △T is temperature change in celsius and c is specific heat capacity in J/kg℃
  - - - The amount of energy per kilogram of material to cause a change of state
    - - m is mass in kg, l is specific latent heat in j/kg