Key Words - You should be able to define and identify the definitions of the terms listed below. They are listed in the order in which they appear in the textbook.

1. matter
2. element
3. atom
4. neutron
5. proton
6. electron
7. atomic nucleus
8. atomic number
9. isotope
10. energy
11. potential energy
12. energy level
13. electron shell
14. orbital
15. valence electron
16. valence shell
17. chemical bond
18. covalent bond
19. molecule
20. structural formula
21. molecular formula
22. double covalent bond
23. valence
24. electronegativity
25. nonpolar covalent bond
26. polar covalent bond
27. ion
28. cation
29. anion
30. ionic bond
31. hydrogen bond
32. chemical reactions
33. reactants
34. products
35. chemical equilibrium