Chemical composition refers to the list of chemical elements or compounds that make up a substance or material, and it expresses the proportions of these elements or compounds in the structure of the substance. The chemical composition of a substance determines its properties and behavior.
Chemical composition describes the types and quantities of atoms found within a substance. Each element has a specific atomic number, and atoms are composed of fundamental particles such as protons, neutrons, and electrons. Compounds are formed when atoms of different elements come together in specific ratios.
For example, the chemical composition of pure water includes the information that it is composed of water molecules (H2O), and each water molecule contains two hydrogen atoms (H) and one oxygen atom (O). In this case, the chemical composition of water is expressed as H2O.
Chemical composition is essential for understanding the properties and reactions of a substance and is one of the fundamental concepts in the field of chemistry.