The Periodic Table (p.160-172)

2. Properties similar to both metals and nonmetals. Example: Silicon
5. The most abundant element in the universe.
10. These elements are the inner transition metals that are all radioactive.
12. A component of chlorophyll.
15. Mendeleev's periodic table gained credibility because he left ______ for elements that were not yet discovered.
17. Group 13 is the ______ family.
18. Can be drawn into wires
21. Dobereiner organized the elements into groups called _______.
23. Good conductors of heat and electric current, found on the left hand side of the periodic table.
24. Group 15 is the ______ family.
25. Elements in Group 3-12. These elements are highly colored metals.
27. The vertical columns in the periodic table.

1. In 1869 this man organized the periodic table in order of increasing atomic mass.
3. The first element to be named after a living person.
4. How many classes of elements are there?
6. Group 16 is the ______ family.
7. When elements are arranged in order of increasing atomic number, there is a periodic repetition of their physical and chemical properties.
8. The horizontal rows in the periodic table.
9. Group 2 elements. Means "the ashes".
11. Group 17 elements. Name is derived from the latin words for "salt" and "genesis"
13. Most of these elements are gases at room temperature. They are found on the right hand side of the table.
14. Group 1 elements.
16. Gases have this color symbol on page 168.
19. Group 14 is the ______ family.
20. In the modern periodic table, elements are arranged in order of increasing _______ _______.
22. Can be hammered into sheets
26. Group 18 elements. They are very unreactive.