
Neither Here nor There

So, if an atom has equal numbers of electrons and protons, the charges cancel each other out and the atom has a neutral charge. You could add a thousand neutrons into the mix and the charge would not change. However, if you add a thousand neutrons, you will be creating one super-radioactive atom. Neutrons play a major role in the mass and radioactive properties of atoms. You may have read the page on isotopes. Isotopes are created when you change the normal number of neutrons in an atom.
Inside the Nucleus

One Special Element
Did we say that all atoms have neutrons? Oops. All elements have atoms with neutrons except for one. A normal hydrogen (H) atom does not have any neutrons in its tiny nucleus. That tiny little atom (the tiniest of all) has only one electron and one proton. You can take away the electron and make an ion, but you can't take away any neutrons. Hydrogen's special structure becomes very important when you learn how hydrogen interacts with other elements in the periodic table. If you learn about nuclear fusion you will learn about deuterium and tritium. Deuterium is a hydrogen atom with an extra neutron and tritium has two extra. You won't find much deuterium in your backyard. It's mainly in oceans. Don't worry if you do find it, it's not radioactive. It's a stable isotope.Related Video...
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