Increasing temperatures cause the molecule in the substance to gain kinetic energy and begin to vibrate and move at high momentum. This allows the molecules in the substance to break from the bonds of the lattice in the solid hence melt to a liquid. More heating gives the molecules more kinetic energy and enables the molecule to further move away from each other and transform to gas.
Explanation:
It is known that the relation between kinetic energy and temperature is as follows.
[tex]K.E \propto \frac{3}{2}kT[/tex]
Therefore, when there will be increase in temperature then there will also occur increase in kinetic energy of the particles of a substance.
Hence, when temperature of a solid substance is increased then its molecules will gain kinetic energy leading to an increase in the number of collisions.
As a result, molecules will start to move away from each other.
Therefore, solid substance will successively convert into liquid substance.
