Короткий опис (реферат):
All that surrounds us is called matter. Matter exists in various states. We should consider two main of them: substance and field (electric, magnetic). These states have opposite properties. For example: diffraction is observed only for waves i.e. field. Main characteristic of the substance is mass. For field it is energy.
All objects are composed of atoms, molecules or ions. Molecule is an electrically neutral group of two or more atoms held together by chemical bonds. Ion can be obtained if an atom or molecule gives away or takes away electrons. So the basic element of matter is the Atom. Understanding the structure of atoms is critical to understanding the properties of matter.
