Neutron Madness

We have already learned that ions are atoms that are either missing or have extra electrons. Let's say an atom is missing a neutron or has an extra neutron. That type of atom is called an isotope. An atom is still the same element if it is missing an electron. The same goes for isotopes. They are still the same element. They are just a little different from every other atom of the same element.

For example, there are a lot of carbon (C) atoms in the Universe. The normal ones are carbon-12. Those atoms have 6 neutrons. There are a few straggler atoms that don't have 6. Those odd ones may have 7 or even 8 neutrons. As you learn more about chemistry, you will probably hear about carbon-14. Carbon-14 actually has 8 neutrons (2 extra). C-14 is considered an isotope of the element carbon.
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Looking at Ions

We've talked about ions before. Now it's time to get down to basics. The atomic number of an element, also called a proton number, tells you the number of protons or positive particles in an atom. A normal atom has a neutral charge with equal numbers of positive and negative particles. That means an atom with a neutral charge is one where the number of electrons is equal to the atomic number. Ions are atoms with extra electrons or missing electrons. When you are missing an electron or two, you have a positive charge. When you have an extra electron or two, you have a negative charge.

What do you do if you are a sodium (Na) atom? You have eleven electrons — one too many to have an entire < ... Read more »

Atoms Are Building Blocks

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 ... Read more »

Atomic Structure

The text provides a historical perspective of how the internal structure of the atom was discovered. It is certainly one of the most important scientific discoveries of this century, and I recommend that you read through it. However, we will begin our discussion of the atom from the modern day perspective.

All atoms are made from three subatomic particles

� Protons, neutron & electrons.

These particles have the following properties: