What happen to the kinetic and potential energy during the boiling and melting?

[Chaos&Anarchy]

I know this question is probably chicken feet to most of the people here, and I hope I am posting on the right thread. But I am just curious about 2 questions;

1 - Where does the kinetic and potential energy comes from in a substance?
2 - How are the kinetic and potential energy affected by boiling or melting?

Any reply would be a real help. Thanks =D

 

[vlado_skopsko]

Substances are composed of atoms or molecules. They are in constant motion (vibrating or translating depending on the state of the substance).
Temperature is the average kinetic energy of a molecule of that substance.
There are connections between the molecules (chemical connections) - potential energy of the substance.
The whole energy of all the molecules (kinetic and potential) is the internal energy of the substance.
If you place another substance(2) in contact with the substance(1) the molecules of the two substances will come in contact and will tend to even their kinetic energies (temperatures).
Heat is the energy that has been transfered.
When a substance goes from one state to another the addition of heat does not increase the temperature of the substance but is used to brake the connections between molecules (to bring the molecules to higher potential level).

From this I hope you can answer those questions.

 

[Chaos&Anarchy]

So basically, while the change of state is occurring only the amount of potential is changed while kinetic energy remains the same? Thanks a lot. That was really helpful.

 

[vlado_skopsko]

Yes, that energy is called latent heat (heat of transformation).
I'm glad I was able to help.

 

[PJC01]

During boiling and melting, both kinetic and potential energy are involved in the process. Kinetic energy is the energy of motion of individual particles, while potential energy is the energy stored in the bonds between particles.

1 - The kinetic and potential energy in a substance comes from the movement and interactions of its particles. At the atomic or molecular level, particles are constantly moving and interacting with each other. This motion and interaction results in the energy that we observe as kinetic and potential energy.

2 - During boiling, the kinetic energy of the particles increases as they gain enough energy to overcome the intermolecular forces holding them together. As the temperature increases, the kinetic energy of the particles also increases, causing them to move faster and further apart. This increase in kinetic energy leads to the conversion of the substance from a liquid to a gas.

During melting, the potential energy of the particles is affected. As the substance is heated, the particles gain enough energy to break the bonds holding them together in a solid state. This results in a decrease in potential energy and a corresponding increase in kinetic energy as the particles begin to move more freely. This change in energy state leads to the conversion of the substance from a solid to a liquid.

In both processes, the total energy of the system (kinetic + potential) remains constant. However, the distribution of this energy changes as the substance undergoes a phase change.