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Atomic Structure


Understanding atomic structure will help you grasp what makes the world work—from creating stink-bombs to radioactivity... plus, it'll help you pass chemistry too.

The atom's center, or nucleus, contains both protons and neutrons. These particles each have a mass of one atomic mass unit (AMU) and together account for the overall weight of the atom. Because protons and neutrons are both in the nucleus of the atom, they are called nucleons. The number of protons and neutrons are very stable, and are not easily changed.

Inside the Atom
So if the nucleons aren't easily changed, what creates atomic reactions? Surrounding the nucleus, electrons (which weigh a negligible amount) orbit in several levels, and combine with electrons in other atoms to create chemical reactions, like the explosions emanating from your school's lab.

The subatomic particles of protons, neutrons, and electrons have charges which explain their atom's behavior. The protons each have a positive charge, and live in the nucleus with neutrons, which each have a neutral charge.

Electrons have a negative charge which counters the charge of protons, creating a neutral atom overall. When electrons are added or subtracted, the atom can become charged either negatively or positively — these kinds of atoms are called ions. Ions then react to each others' electrical nature.

Now you try it...

Bullet   Atomic Structure Practice Qs
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