Definition - What does Chemical Reaction mean?
A chemical reaction is a process that causes changes in substances, which results in new compounds that have a different chemical identity and properties than before the reaction. The process changes atoms' electron positions, but do not change its nuclei. Chemical reactions change physical properties of the new products such as solid, liquid or gas, if it emits heat and light, and if it forms precipitate and changes colors.
Safeopedia explains Chemical Reaction
Chemical reactions cause chemical changes and produce one or more products. It can easily be described with a chemical equation that shows materials before and after the reaction. Chemical reactions sometimes need heat or catalysts in order to occur. Some reactions are extremely fast while some are very slow. Consider, for example:
C+O2 = CO2 (when carbon is burned in oxygen, it produces carbon dioxide).
Here, carbon and oxygen are two different elements burned in a chemical reaction and produce carbon dioxide, which has different properties than carbon or oxygen.
Chemical reactions are used in processing and transforming while making products in many industries. Since these produce and emit various energy, therefore, these are to be made safe in the workplace. One of the compliance requirements of the industrial regulations is to ensure safety of the workers from all types of hazardous chemicals and chemical processes.