Atomic structure

All matter is composed atoms which contain electrons neutrons and protons. The electrons are in the outside cloud and the neutrons and protons are in the nucleus in the center of the atom.  Electrons are a part of all forms of matter because they are attracted the the positively charged nucleus. Most of an atom consists of electrons moving rapidly through empty space. The electrons move throughout the available space around the nucleus and are held in the atom atom by their attraction to the positively charged nucleus. The volume of the space which they move in is huge compared to the volume of the nucleus. A tiny hole located in the center of the anode produces a thin beam of electrons A phosphor overcoating allows the position of the beam to be determined as it strikes the end of the tube. Because altering the gas in the tube and the material used for the cathode have no effect on the cathode ray, the particles in the ray must be part of all matter. People usually write out isotopes using a shortened type of notation involving the chemical symbol, atomic number, and mass number. The mass number is written as a superscript to the left of the chemical symbol, and the atomic number is written as a subscript to the left of the chemical symbol. You can't pass your hand through a solid object because they're so tightly packed together unlike a liquid or gas.

Here is this picture as an example: