The Periodic Table

2. metalloid found at the top of group 3
5. metals found in the earth with 2 valence electrons
7. these are unstable isotopes used in medicine and to generate electricity
12. all elements in group 5 are solid at room temperature except this element
14. charge when an atom has more protons than neutrons
15. heaviest part of the atom containing protons and neutrons
17. group 7 elements are known as
18. last group in the periodic table
19. element at the top of group 6
20. different atoms of the same element
21. these sub-atomic particles have no weight
23. this element stands alone but is sometimes placed in group 1

1. vertical columns in the periodic table
3. group in the periodic table with 4 valence electrons
4. smallest component of an element
6. metals most reactive metals with one outermost electron
8. horizontal rows numbered 1-7
9. chemical property that determines how elements react with each other
10. formed when an atom gained/loses electrons
11. outer most electrons called _____ electrons
13. these elements have both metallic and non- metallic properties;found in zig zag pattern
16. metals with varying numbers of valence electrons found between groups 2 and 3
22. these metals are found in the first row beneath the transition metals