Chemistry

2. The distance from the nucleus to the outermost electrons of an atom.
6. A positively charged ion formed when an atom loses electrons.
7. The amount of energy required to remove an electron from an atom.
8. Elements that are shiny, conductive, and tend to lose electrons.
10. Elements that are dull, poor conductors, and tend to gain electrons.
11. Electrons fill orbitals singly before pairing up in the same orbital.
12. A negatively charged ion formed when an atom gains electrons.
14. A diagram that shows valence electrons as dots around the chemical symbol.
15. Elements that have properties of both metals and nonmetals.
18. An atom or group of atoms that has gained or lost electrons.
19. The ability of an atom to attract electrons in a chemical bond.

1. Having the same number of electrons or same electron configuration as another atom or ion.
3. Principle Electrons fill the lowest energy levels first before moving to higher levels.
4. Elements in Group 18 that are unreactive due to full valence shells.
5. A model of the atom where electrons orbit the nucleus in specific energy levels.
9. The outermost electrons of an atom that determine its chemical properties.
11. Elements in Group 17; very reactive nonmetals that form salts with metals.
13. Exclusion Principle No two electrons in the same atom can have the same set of quantum numbers.
16. A diagram showing how valence electrons are arranged in bonds around atoms.
17. Elements in Group 1 of the periodic table; highly reactive metals.