How do particle vibrations change during the melting of a solid?

During the melting of a solid, particle vibrations increase, causing particles to move more freely and break their fixed positions.

In a solid state, particles are closely packed together in a regular pattern and vibrate around fixed positions. They do not have much freedom to move around due to the strong intermolecular forces holding them together. The energy of these particles is primarily in the form of vibrational energy.

When heat is applied to a solid, it is absorbed by the particles, causing them to vibrate more vigorously. This increased vibration is due to the particles gaining kinetic energy. As the temperature rises, the vibrations become so intense that the particles have enough energy to overcome the strong intermolecular forces that were holding them in their fixed positions.

This is the point at which the solid begins to melt and turn into a liquid. The particles start to move more freely and slide past each other, but they still remain close together. The regular pattern of the solid is lost, and the substance takes on the shape of the container it is in, characteristic of a liquid state.

It's important to note that during this process, the temperature of the substance remains constant. This is because all the energy supplied is used to overcome the intermolecular forces, rather than to increase the temperature. This period of constant temperature during a change of state is known as a plateau on a heating curve.

In summary, the melting of a solid involves an increase in particle vibrations due to the absorption of heat energy. This leads to the particles breaking free from their fixed positions and moving more freely, resulting in the transition from a solid to a liquid state.