To understand what a chemical reaction is, one needs to begin by knowing that molecules are made up of atoms. Chemical bonds secure the atoms together to form a molecule. Molecules are minuscule particles and are chemically bonded. They are neutral and do not have an electrical charge. Also, a molecule must have at least two or more atoms.
For a chemical reaction to occur, a molecule has to change. If a molecule is going to change it has to interact with another or other molecules. Change occurs when atoms are broken apart resulting in new molecules. The chemical change is like magic because when molecules react to an agent that serves as a catalyst for change, the atoms break-up, the molecule changes and takes a new form.
An agent that initiates change can be heat or heat created when chemicals are combined. A chemical reaction cannot usually be reversed. For example, when a fire burns wood, the wood can not undergo a chemical reaction to rebecome wood. The wood remains ashes. Tearing paper is not a chemical change because the paper can be taped back together, but if the paper is burned, a chemical reaction occurs. When hydrogen and oxygen are combined, a chemical reaction called a synthesis reaction occurs, and water is created.
A chemical reaction is a reaction where there is a change where a new matter is formed.
Example: rusting, burning, decomposing, fermenting
A chemical reaction is not to be confused with a physical reaction, where there is a visible change in appearance without a change in the composition.
Example: boiling, melting, cutting, bending, splitting, cracking
A chemical reaction takes place within the structure of an element of compound. In a chemical reaction, the atoms are rearranged and changes in the bonding occurs. The reactants, or chemicals, undergo a change, and a new product is made. The atoms rearrange to create the new compounds. Most times a chemical reaction cannot be reversed, but sometimes the application of electricity allows for it to be reversed. There are foye main clues that can help someone identify if a chemical reaction has occurred. These clues include, an unexpected color change, gas given off, unexpected temperature change, or a percipitate forming. Common examples include burning wood into charcoal and rusting of nails.