| A | B |
|---|
| atom | the smallest component of an element having the same properties of the element |
| nucleus | the central core of an atom containing protons and usually neutrons. |
| proton | a small, positively charged particle in the nucleus of the atom. |
| neutrons | a small particle in the nucleus of the atom, with no electrical charge. |
| electrons: | a tiny, negatively charged particle that moves around the nucleus of an atom |
| isotope | two or more elements that contains the same number of protons but different number of neutrons. |
| ion | a charged atom, with more or less electrons than neutrons. |
| atomic number | the number of protons in the nucleus of an atom. |
| atomic mass | the average mass of one atom of an element. |
| Bohr Model | a model of the atom which shows the energy levels or rings of an atom |
| valence electrons | the electrons in the outermost electron level or orbital (highest energy level) of the electron. |
| Energy Levels | the possible energies that electrons in an atom can have |
| Electron Cloud | a visual model of the most likely locations for the electrons in an atom |
| Orbital | region of space around the nucleus where an electron is likely to be found |
| Electron configuration | the arrangement of electrons in the orbitals of an atom |
| Ground State | a state in which all the electrons in an atom have the lowest possible energies |
