When matter is heated, the kinetic energy of its particles increases. Heating a substance provides energy that causes the particles within that substance to move more vigorously. As the temperature rises, the average kinetic energy of the particles increases, leading to more rapid motion, which can be observed as increases in vibration, rotation, and translation of the particles.
In solids, the particles vibrate more intensely around fixed positions, while in liquids, they can move past each other more freely. In gases, the particles move even more freely and rapidly, occupying more space and colliding with each other and the walls of their container more frequently. This increase in the kinetic energy of the particles also correlates with an increase in temperature, as temperature is a measure of the average kinetic energy of the particles in a substance.
In summary, heating matter elevates the kinetic energy of its particles, causing increased motion and leading to changes in physical state and material properties.