A chemical reaction involves the rearrangement of atoms and the formation of new chemical substances, resulting in a change in the chemical composition of the substances involved. In other words, the original substances are transformed into entirely new substances with different properties. Chemical reactions usually involve the breaking and forming of chemical bonds.
On the other hand, a physical change refers to a change in the physical properties of a substance, such as its shape, size, or state of matter, without any change in its chemical composition. Physical changes do not involve the formation of new substances or the breaking of chemical bonds. Examples of physical changes include melting, freezing, boiling, dissolving, or changes in state (solid, liquid, gas).
In summary, the key difference between a chemical reaction and a physical change lies in whether there is a change in the chemical composition of the substances involved. Chemical reactions involve a change in chemical composition, while physical changes do not.
One reply on “Chemistry”
Beautiful !