What is physical change and chemical change ?
Physical Change Those changes in which no new substances are formed, are called physical change. In a physical change the substances involved do not change their identity. They can be easily return to their original form by some physical process. This means that physical change can be easily reversed. The change in physical state, size and shape of a substance are physical changes. Some common examples of physical changes are : melting of ice, freezing of water, boiling of water, condensation of steam, making a solution, glowing of an electric bulb and breaking of a glass tumbler. The physical changes are temporary changes which can be reversed easily to form the original substance. For example the melting of ice to form water is a temporary change we can reverse this physical change easily by cooling water to form the original substance, ice. Some more examples of physical changes are Melting of ice; Melting of butter; Melting of...