An atom or group of atoms that has a positive or negative electric charge because it has lost or gained...

1. An atom or group of atoms that has a positive or negative electric charge because it has lost or gained electrons is a(n) ________.
2. The sodium ion has ________ protons, ________ neutrons, and ________ electrons.
3. In most chemical reactions, atoms tend to match the outer electron configuration of the noble gases. This is called the ________ rule.
4. An anion is an ion with a ________ charge.
5. ________ electrons occupy the outermost energy level of an atom.
6. The chloride ion and the chlorine atom have ________ electron configurations.
7. A cation is an ion with a ________ charge.
8. Many stable ions have an electron configuration of a ________.
9. How do the outer-shell electron configurations for ions of Group 1, Group 2, and Group 15, Group 16, and Group 17 elements compare with those of the noble gases?