Internal Energy and Change of State

• What is internal energy?

  The total energy of a system, including both its kinetic and potential energy.
• What happens to particles in a substance when that substance is heated?

  They gain energy and move faster.

  Vibrate, get further apart, change state is temperature meets it’s melting/boiling points
• Name the five changes of state

  melting, (Solid —> Liquid)

  freezing, (Liquid —> Solid)

  sublimation, (Solid —> Gas)

  deposition, (Gas —> Solid)

  condensation, (Gas —> Liquid)

  vaporisation, (Liquid —> Gas)
• Define specific latent heat of fusion:

  The amount of energy needed to change the state of 1kg of a substance from solid to liquid