3.2.2 Internal Energy

• What type of energy increases with temperature?

  Kinetic
• The kinetic energy of molecules depends on their temperature and molecular mass
• Match the component of internal energy with its description:

  Kinetic energy ↔️ Energy due to molecular motion

  Potential energy ↔️ Energy stored in molecular bonds
• Internal energy refers to the total energy that molecules within a substance possess
• Potential energy changes during phase transitions.


  True
• What type of energy is stored in molecular bonds?

  Potential
• The sum of kinetic and potential energy equals internal energy.


  True
• How does temperature affect the kinetic energy of molecules?

  Increases it
• Potential energy depends on the phase of the substance.


  True
• Match the phase change with the energy type changed and its effect:

  Solid to Liquid ↔️ Potential energy increases

  Liquid to Gas ↔️ Potential energy increases significantly
• Internal energy consists of kinetic and potential energy.


  True
• The latent heat involved in phase transitions changes the potential energy without altering the kinetic energy.
• What is the primary factor that affects kinetic energy in a substance?

  Temperature
• Match the component of internal energy with its description:

  Kinetic energy ↔️ Energy due to molecular motion

  Potential energy ↔️ Energy stored in molecular bonds
• Kinetic energy increases with higher temperatures and lower molecular masses.


  True
• Lighter molecules have higher kinetic energy due to their lower mass.
• Potential energy depends on the phase of the substance and the strength of intermolecular forces.


  True
• During boiling, energy is absorbed to weaken bonds, increasing the potential energy.
• Arrange the phases of matter from lowest to highest potential energy:

  1️⃣ Solid

  2️⃣ Liquid

  3️⃣ Gas
• During a liquid to gas transition, potential energy increases as intermolecular bonds weaken.
• Latent heat changes potential energy without altering kinetic energy.

  True
• Kinetic energy increases with higher temperatures and lower molecular masses
• Kinetic energy increases with higher temperatures and lower molecular masses
• Order the following factors based on their effect on kinetic energy:

  1️⃣ Lower molecular mass

  2️⃣ Higher temperature
• During changes of state, potential energy changes while kinetic energy remains constant
• What is the energy used during phase transitions called?

  Latent heat
• What happens to intermolecular bonds during a liquid to gas phase transition?

  They weaken
• Internal energy consists of kinetic and potential energy.


  True
• Potential energy changes during phase transitions as intermolecular forces are altered.
• What forms the total internal energy of a substance?

  Kinetic and potential energy
• What effect does temperature have on the kinetic energy of molecules?

  It increases
• Why do lighter molecules have higher kinetic energy at the same temperature?

  They move more freely
• Match the phase with its intermolecular forces and potential energy:

  Solid ↔️ Strong forces, low potential energy

  Liquid ↔️ Moderate forces, moderate potential energy

  Gas ↔️ Weak forces, high potential energy
• What happens to potential energy during freezing?

  It decreases
• What remains constant during a phase change?

  Kinetic energy
• How is temperature measured?

  Celsius or Kelvin
• Internal energy is the total energy of a substance, while temperature measures the average kinetic energy.