Chemical vs Physical Processes

Every change that occurs in nature can be described in one of two ways: physical or chemical.  Physical processes are changes in nature that result in an object changing in appearance, shape, form, color, etc., but the object retains its chemical substance and composition. No chemical reaction takes place during physical processes. One example of a physical process is the evaporation of water. When water evaporates, a group of water molecules changes from the liquid to the gas state, but they are still water molecules. Chemical processes are changes in nature that result in an object not only going through a physical process but also involve a fundamental change in the object’s composition. A chemical reaction takes place during chemical processes. Any process that involves a chemical reaction, such as combustion or acid-base reactions, is a chemical process. In almost every case, physical processes are reversible whereas chemical processes are irreversible.  Another difference between the two is that physical processes involve little amount of energy exchange whereas chemical processes usually involve a greater amount of energy.