What Is the Relationship Between Elements and Atoms?

Atoms are the building blocks of everything that exists. From the clothes on your back to the car you drive to the food you eat—everything is composed of atoms. Each individual atom belongs to only one element. This is to say that even though there are an incomprehensible number of atoms on this planet and the universe making up everything we know and are yet to know, all of these atoms belong to only one of a hundred or so
elements (see Appendix A). This is similar to each one of the billions of people living on this planet being native to only one of a hundred or so countries.
 

In a world where size is judged relative to the size of humans, the atom is indeed minuscule. It has been said that if we could line up a million atoms end to end they would barely cover the distance across the period at the end of this sentence. However, they do indeed exist even though you cannot see them with the naked eye.
 

All atoms have a similar blueprint to the image displayed in Figure 1.1. There are three principal particles called neutrons, protons, and electrons. Because they are smaller than the atom that they come together to form, they are often called subatomic particles. Protons bear a positive charge (+) while electrons have a negative charge (−) and neutrons do not bear any charge at all. By design an element has the same number of electrons as protons and is said to be neutral. However, as we’ll see next that isn’t how many atoms exist naturally.