Click on the and find periodic table icon, . Click and view the periodic table as we know it today. Click on a few of the elements on the periodic table and find out the element's name, its atomic number and its atomic mass. You'll be using the periodic table quite often throughout the course.

There are seven periods of elements in the periodic table.

Each period has a variation in physical and chemical properties. It starts with reactive metals on the left side and ends with the nonreactive noble gas on the right side.

The number of the period gives the number of the outermost principal energy level that the valence electron(s) occupies. This is best illustrated by reviewing the arrangement of electrons in principal energy levels and the Bohr diagrams.

Need a review? (section 3.3.1)

Take a look at a few examples:

Follow these interesting links:

	A short history of the periodic table.
	View the early periodic table, Mendeleev's periodic table