| A | B |
|---|
| atom | the smallest division of a type of thing |
| element | a type of atom with a unique number of protons |
| compound | different types of atoms joined together |
| molecule | multiple atoms joined together |
| electron cloud | the outer region of the atom where electrons are found |
| nucleus | the center of the atom where protons and neutrons are found |
| radiation | unstable isotopes decay into smaller atoms |
| isotope | a version of an atom with a different number of neutrons |
