Changes of Heat and Specific Latent Heat

• What is the term for the energy needed for a substance to change state?

  Latent heat
• What happens when a change of state occurs?

  Energy is needed for the change
• What is the energy supplied during a change of state called?

  Latent heat
• What does the energy supplied during a change of state not affect?

  Temperature of the substance
• What does the specific latent heat of a substance represent?

  Energy required to change state of 1 kg
• How is the energy for a change in state calculated?

  Energy = mass x specific latent heat
• What is the formula for energy during a change of state?

  $E =$$mL$
• What does the variable 'm' represent in the energy formula?

  Mass of the substance in kilograms
• What does the variable 'L' represent in the energy formula?

  Specific latent heat in joules per kilogram
• How does the specific latent heat of fusion differ from that of vaporization?

  Fusion is solid to liquid, vaporization is liquid to gas
• What is the specific latent heat of vaporization?

  Energy required to change liquid to gas
• What is the specific latent heat of fusion?

  Energy required to change solid to liquid
• What is the significance of latent heat in phase changes?

  It allows substances to change state without temperature change
• What are the types of phase changes and their specific latent heats?

  • Fusion: solid to liquid
  • Vaporization: liquid to gas
  • Latent heat of fusion: energy for solid to liquid
  • Latent heat of vaporization: energy for liquid to gas
• What is the change of state from solid to liquid called?

  Fusion
• What is the change of state from liquid to gas called?

  Vaporization
• What is the change of state from liquid to solid called?

  Freezing
• What is the change of state from gas to liquid called?

  Condensation
• What happens during vaporization?

  Liquid absorbs energy to become gas
• What happens during condensation?

  Gas releases energy to become liquid
• What happens during freezing?

  Liquid releases energy to become solid
• What happens during melting?

  Solid absorbs energy to become liquid
• What are the differences between latent heat of fusion and latent heat of vaporization?

  • Latent heat of fusion: solid to liquid
  • Latent heat of vaporization: liquid to gas
  • Fusion occurs at melting point
  • Vaporization occurs at boiling point