PhET Simulation: Atomic Interactions

Overview

• Uses PhET simulation for atomic interactions.
• Key focus on chemical potential energy and atomic forces.

Simulation Setup

• Graph with:
  • X-axis: Distance between atomic nuclei.
  • Y-axis: Chemical potential energy of the system.
• Two neon atoms:
  • Left neon atom fixed.
  • Right neon atom movable.

Observations with Neon Atoms

• Atoms apart:

  • Atoms initially move towards each other, speed up, then bounce off.
  • Green arrows indicate forces:
    • Far apart: Determine if force is attractive or repulsive.
    • Close proximity: Determine if force changes.

• Total Force Analysis:

  • Find distance where net force is zero (bottom of the potential energy well).
  • Examine energy input/output to move atoms.

• Individual Forces:

  • Orange arrows: Attractive forces.
  • Pink arrows: Repulsive forces.
  • Far apart: Attractive force stronger than repulsive.
  • Close proximity: Repulsive force stronger.
  • Bottom of Well: Forces are equal, no net force.

Comparison with Oxygen Atoms

• Graph Differences:
  • Oxygen graph exceeds previous scale.
  • Upon release, oxygen atoms stay together unlike neon atoms.
• Analysis:
  • Identify differences between neon and oxygen atomic interactions.
  • Consider why differences occur.

Chemical Reaction: Methane Combustion

• Reactants:

  • Methane + Oxygen.
  • Products: Carbon dioxide + Water.

• Energy Changes:

  • Breaking Bonds: Increases energy (moves up on graph).
  • Forming Bonds: Decreases energy (moves down on graph).

• Exothermic Reaction:

  • Overall energy release as products are in lower energy state.

Conclusion

• Reflect on differences between neon and oxygen atomic interactions.
• Application to understanding chemical reactions such as methane combustion.
• Refer to simulation link for further exploration, including argon-argon interactions.