Chemical reaction is synonymous to a chemical change. A chemical change is one which is not easily reversed and in which a new substance is formed.
The reactants are converted to products by the rearrangement of the constituent atoms to form a different compound.
Examples include burning of fuel, smelting of iron.
Physical change is different from chemical change as it involves a change of state or phase and the chemical properties of its constitients elements are intact. Unlike in chemical change where there is a change in the chemical properties of the new products formed
