Periodic Table

1. Arrangement of elements in columns, based on a set of properties that repeat from row to row
7. an ion with a positive charge
12. Groups 1, 2, 13-18
13. Created the first periodic table. Arranged elements by increasing atomic mass
14. Elements that are good conductors of electric currents and heat
15. the law that states that the repeating chemical and physical properties of elements change periodically with the atomic numbers of the elements
17. The name for each column on the periodic table
18. an ion with a negative charge
19. Elements that form a bridge between the elements on the left and right sides of the table

2. The amount of energy required to remove an electron from an atom
3. Electrons that are in the highest occupies energy level of an atom
4. This group has an electron configuration that ends with ns^2
5. the ability of an atom to attract electrons when the atom is in a compound
6. This group has an electron configuration that ends with ns^2 np^5 and they are the most reactive nonmetals
8. Group 18 nonmetals with eight valence electrons (Helium has only two valence electrons) that are very stable, colorless, odorless, and extremely unreactive
9. Elements that are poor conductors of heat and electric current
10. Elements with properties that fall between those of metals and nonmetals
11. size of an atom
15. The name for each row in the table of elements
16. Group 1 Metals with a single valence electron and are extremely reactive