Atoms are the basis of chemistry. They are the basis for everything in the Universe. You should start by remembering that matter is composed of atoms. Atoms and the study of atoms are a world unto themselves. We''re going to cover basics like atomic structure and bonding between atoms. As you learn more, you can move to the biochemistry pages and see how atoms form compounds that help the biological world survive.

Smaller Than Atoms?

Are there pieces of matter that are smaller than atoms? Sure there are. You''ll soon be learning that atoms are composed of pieces like electrons, protons, and neutrons. But guess what? There are even smaller particles moving around in atoms. These super-small particles can be found inside the protons and neutrons. Scientists have many names for those pieces, but you may have heard of nucleons and quarks. Nuclear chemists and physicists work together at particle accelerators to discover the presence of these tiny, tiny, tiny pieces of matter.

Even though super-tiny atomic particles exist, you only need to remember the three basic parts of an atom: electrons, protons, and neutrons. What are electrons, protons, and neutrons? A picture works best to show off the idea. You have a basic atom. There are three types of pieces in that atom: electrons, protons, and neutrons. That''s all you have to remember. Three things! As you know, there are almost 120 known elements in the periodic table. Chemists and physicists haven''t stopped there. They are trying to make new ones in labs every day. The thing that makes each of those elements different is the number of electrons, protons, and neutrons. The protons and neutrons are always in the center of the atom. Scientists call the center region of the atom the nucleus. The nucleus in a cell is a thing. The nucleus in an atom is a place where you find protons and neutrons. The electrons are always found whizzing around the center in areas called shells or orbitals.

You can also see that each piece has either a "+", "-", or a "0." That symbol refers to the charge of the particle. Have you ever heard about getting a shock from a socket, static electricity, or lightning? Those are all different types of electric charges. Those charges are also found in tiny particles of matter. The electron always has a "-", or negative, charge. The proton always has a "+", or positive, charge. If the charge of an entire atom is "0", or neutral, there are equal numbers of positive and negative pieces. Neutral means there are equal numbers of electrons and protons. The third particle is the neutron. It has a neutral charge, also known as a charge of zero. All atoms have equal numbers of protons and electrons so that they are neutral. If there are more positive protons or negative electrons in an atom, you have a special atom called an ion.