The rate of change in ice melting is a result of its surface area, which is related to its shape. Because it represents a point of contact with another substance at a higher temperature, differences in surface area affect the melting rate of ice proportionately. A thin sheet of ice, which has a greater degree of surface area, will melt faster than a cube of ice that is of a similar volume.
The common term "melting" describes one of the physical processes referred to in chemistry and physics as "phase transition," in which a substance is changed from one physical state to another by an increase or decrease of its internal energy. One of the scientific criteria regarded as a qualifier for a substance melting is the amplitude of the internal vibrations within a solid substance reaching a point where vibrational instability causes the crystal structures to come apart.
Intermolecular forces, or IMF, are the binding forces that cause the water molecules in ice to rotate around fixed positions. Adding heat to ice raises the internal kinetic energy level. The increased internal vibrations enable the water molecules to slide freely past each other, and they assume the liquid physical stage of water. If the temperature is increased far enough past the point at which water assumes its liquid stage, the internal energy will enable the water molecules to move independently of each other. At this point, water assumes the gaseous state commonly referred to as water vapor or steam.