Answer:
See explanation
Step-by-step explanation:
a) Every substance melts at a particular temperature known as the melting point of the substance. The melting point of ice is 0°C. Hence ice melts at 0°C.
b) There are three states of matter; solid liquid and gas. The particles of matter in each stage of matter possess varying degrees of freedom.
In the solid state, the intermolecular forces between the particles of water that compose ice are very strong. Hence the particles do not translate, they only vibrate or rotate about their mean positions.
In the liquid state, the magnitude of intermolecular interaction is less than that of the solids hence the molecules can translate but not with a high kinetic energy.
In the gaseous state, there is a minimum intermolecular interaction between particles theoretically hence the particles are really free to move about with a very high kinetic energy.