Chemical reaction is a process of interconversion of some substances into other substances. The substances present before chemical reaction are called reactants and the substances produced as a result of chemical reaction are known as products. There are five main signs of chemical reaction. The of color of reactants indicates the chemical reaction. Properties are changed during a reaction. Chemical reaction takes place when energy of the system changes. Temperature of system changes in a chemical reaction. During some reactions, precipitates are formed. Moreover, sometimes gases are evolved during a chemical reaction and bubbles are produced, which indicates the completion of reaction.
