1. The periodic table of elements includes information on many different types of elements. What are the four key pieces of information that is included with a single element in most periodic tables? (2 pts.) 2. What is the atomic weight of oxygen? (1 pt.) 3. Explain the electronegativity trends in the periodic table. (1 pt.) 4. What is the key difference between ionic bonds and covalent bonds? (1 pt.) 5. What is the phenomenon known as when a forward chemical reaction occurs at the same rate of a reversible chemical reaction? (1 pt.)