Energy of matter

• Changes of state and conservation of mass

  Changes of state are physical changes because no new substances are produced.The mass always stays the same because the number of particles doesn't change
• Particles and kinetic energy


  When the temperature of a substance is increased, the kinetic energy store of its particles increases and the particles vibrate or move faster

  If the kinetic energy store of a substance's particles increases or decreases enough, the substance may change state
• Density(kg/m^3) =mass(Kg) /volume(m^3)
• Arrangement of gases


  Particles spread out

  Almost no forces of attraction
• Movement of gases


  Particles move randomly at high speeds
• Properties of gases


  low density

  no fixed volume or shape

  Can be compressed and can flow

  Spread out to fill all available space
• Arrangement of liquids


  Particles are in contact with eachother

  Forces of attraction are weaker than solids
• Movement of liquids


  Particles are free to move randomly around eachother
• Properties of liquids


  low density

  Fixed volume

  Shape isn't fixed so they can flow
• Arrangemnet of solids


  Particles held next to eachother in fixed positions by strong forces of attraction
• Movement of solids


  Particles vibrate about fixed positions
• Properties of solids


  high density

  Fixed volume

  fixed shape unless deformed by external force
• Internal energy


  sum of total kinetic energy particles have and total potential energy particles have due to their positions relative to eachother

  can be increased by heating a substance
• latent heat


  energy transferred when a substance changes state
• energy transfers during a change in state don't cause a change in temperature but do change the internal energy of a substance
• Specific latent heat


  energy required to change the temperature of 1Kg of a substance with no change in temperature
• Specific latent heat of fusion

  energy required to melt 1 Kg of a substance with no change in temperature
• specific latent heat of vaporisation


  energy required to evaporate 1 Kg of a substance with no change in temperature
• thermal energy for a change in state(J)=mass(Kg)*specific latent heat(J/Kg)