Structure and Properties of Matter
All things, whether living or not, are made of atoms. These atoms are composed of a positively charged nucleus and negatively charged electrons that orbit the nucleus in a stable manner. Each material is made up of bonds between different atoms, and their properties depend on the kind of atom and how they are organized.
The way the atoms of a substance are distributed in space defines the distribution of electrons along the material – its electronic structure – and it is from this structure that the macroscopic properties of a material depend whether it will be rigid or malleable, opaque or transparent, or even conductor, semiconductor or insulation. For example, two materials with completely different properties, such as diamond and graphite, are composed of the same carbon atoms. The only difference is the distribution of these atoms in space.
In order to investigate the properties of various materials it is necessary to know the atoms that compose them and how they are distributed. Just as we use visible light to observe the macroscopic properties of things, their shape and color, it is possible to use the various electromagnetic waves to investigate the structure, composition, and properties of things on the microscopic scale, with much greater precision than our eyes.