heating and cooling graphs

• What should you be able to do by the end of the video?

  Interpret heating and cooling graphs
• What is internal energy?

  Energy stored inside a system by particles
• What types of energy are included in internal energy?

  Kinetic and potential energy of particles
• What does potential energy depend on in a substance?

  Forces between particles and atomic bonds
• What happens to the temperature of a solid as it is heated?

  • Temperature rises as energy increases
  • Eventually becomes horizontal at melting point
• What is the term for the graph showing temperature changes during heating?


  Heating graph
• What occurs at the melting point on a heating graph?

  The solid changes state to a liquid
• What is the energy needed for a substance to change state called?

  Latent heat
• What happens to the internal energy during a change of state?

  It increases but temperature remains constant
• How can you find the melting point from a heating graph?

  By reading off the horizontal line
• What happens after all the solid has melted?

  The temperature starts to rise again
• What occurs at the boiling point on a heating graph?

  The liquid changes state to a gas
• What is the term for the graph showing temperature changes during cooling?

  Cooling graph
• What is condensation in terms of state change?

  Gas changing to a liquid
• What is freezing in terms of state change?

  Liquid changing to a solid
• What are the key points to interpret heating and cooling graphs?

  • Identify temperature changes
  • Recognize state changes (melting, boiling, condensation, freezing)
  • Understand latent heat and internal energy changes