Atoms can gain or lose electrons in the outer shell, or share them with other atoms by bonding. Each atom has a characteristic valence, based on the number of electrons in the outer shell.
Full shells are relatively stable.
These valences determine the physical and chemical properties of an element. The vertical columns of the Table list groups and families. The Periodic Chart will give you more detailed information about the properties of matter, periodic properties, and some of the major groups on the chart. Finish up with an Interactive Periodic Table of the Elements for a handy reference as you answer the questions below 2. Now test yourself by trying to fill in all the elements on The Periodic Table Challenge 4.