A physical change is a change in which no new substances are formed and most physical changes are reversible. Examples: changes of shape, changes of states, passing electricity through a copper wire. Special details which do not change in a substance without new substances being formed are called physical properties. e.g. change of water into ice or water vapor, change of density.Paraffin wax, which is solid before heating and liquid after heating. Some physical changes are melting, freezing, boiling.