1. Elastic Collisions:
* Low Energy: If the collision is at low energy, the atoms will simply bounce off each other. This is called an elastic collision, where kinetic energy is conserved.
* Higher Energy: At slightly higher energies, the atoms can still bounce off each other, but some energy might be transferred into vibrational or rotational modes of the atoms. This is still considered an elastic collision as the total energy is conserved, just redistributed.
2. Inelastic Collisions:
* Even Higher Energy: If the atoms collide with enough energy, they can combine to form a hydrogen molecule (H₂). This is called an inelastic collision, as energy is lost and converted into the formation of the chemical bond.
* Very High Energy: At extremely high energies, the collision might lead to ionization, where an electron is stripped from one of the hydrogen atoms, creating a proton and a free electron.
3. Other Reactions:
* Nuclear Fusion: In specific conditions, such as extremely high temperatures and pressures, the collision of hydrogen atoms can lead to nuclear fusion, where two hydrogen atoms fuse to form helium, releasing a tremendous amount of energy. This is the process that powers stars.
In summary, what happens when hydrogen atoms collide depends on the energy of the collision. At low energies, they bounce off each other. At higher energies, they can form a hydrogen molecule. At very high energies, they can ionize or undergo nuclear fusion.
