Latent heat is the amount of heat energy that is required to cause a change in state of matter without any change in temperature. This means that during a phase change, such as melting or boiling, the temperature of the substance remains constant while the particles absorb energy to overcome intermolecular forces and change their arrangement.

On the other hand, kinetic energy is the energy that is possessed by particles due to their motion. During a phase change, the kinetic energy of the particles does not increase even though they are absorbing energy, because the energy is used to break down intermolecular forces and not to increase the speed of the particles.



Cohesion is the force of attraction between particles of the same substance. In order to overcome this force, the particles need to absorb energy which is provided by the heat source. During a phase change, the temperature of the substance remains constant because all the energy that is absorbed by the particles is used to overcome the cohesive forces and not to increase the kinetic energy of the particles.

For example, when ice melts, the temperature remains at 0°C because the heat energy is used to break the hydrogen bonds between the water molecules, which hold the particles in a fixed position. Once enough energy is absorbed, the particles start to move more freely and take on a liquid form.

Similarly, when water boils, the temperature remains at 100°C because the energy is used to break the intermolecular forces between the water molecules in the liquid state. The energy causes the particles to move faster and eventually break free from the liquid, forming a gas.



In conclusion, during a phase change, the particles absorb energy to overcome intermolecular forces and change their arrangement without any increase in kinetic energy. The energy absorbed is used to break down the cohesive forces between particles. This leads to a constant temperature and a change in state of matter.

During the conversion of state from one to another, it is the temperature that remains constant, the heat supplied is used to increase the K.E. which in turn helps the particles overcome the cohesion between them.