What happens to particles during melting?

During melting, particles gain energy and move from a fixed, orderly arrangement to a more random, fluid state.

When a solid substance is heated, its particles absorb energy. This energy causes the particles to vibrate more vigorously. In a solid, particles are arranged in a fixed, orderly structure, often forming a crystal lattice. These particles are held together by strong intermolecular forces, which keep them in place.

As the temperature increases, the particles gain more kinetic energy. Eventually, the energy becomes sufficient to overcome the intermolecular forces holding the particles in their fixed positions. At this point, the solid begins to melt. The particles start to move more freely, sliding past one another, which is characteristic of a liquid state. This transition from a solid to a liquid is known as melting.

During the melting process, the temperature of the substance remains constant at its melting point. All the energy supplied is used to break the intermolecular bonds rather than increasing the temperature. This is why, for example, ice remains at 0°C while it melts, even if you continue to apply heat.

In summary, during melting, particles transition from a fixed, orderly arrangement to a more random, fluid state by gaining energy and overcoming intermolecular forces. This process involves a constant temperature where the energy input is used to change the state rather than increase the temperature.