Periodic Table

2. a substance having a finite activation energy (band gap) for electron conduction
5. fixed distances from the nucleus of an atom where electrons may be found
7. the basic unit of a chemical element
9. an atom or a molecule that has a positive or negative electrical charge
10. an ion with negative charge
11. devised the periodic table
16. an ion with positive charge
17. the number of protons in each atom
18. An element that is not a metal but that has some properties of metals
19. A small, positively charged particle of matter found in the atoms of all elements

1. the electrons in the outermost shell, or energy level, of an atom
3. a simple substance that cannot be broken down into smaller parts or changed into another substance
4. an element that readily forms cations and has metallic bonds
6. the quantity of matter contained in an atom of an element
8. measure of its atomic mass/ atomic mass unit
12. a horizontal row of the periodic table
13. odorless, colorless, nonflammable, and monotonic gases that have low chemical reactivity
14. A verticle column in the periodic table
15. the particles in an atom that have a neutral charge