What's In the Box :


Tool: Interactive Periodic Table

The Periodic Table of the Elements can be a very useful tool for you in both school and life, if you understand how to read it. The table is organized into horizontal rows called periods that read from left to right, just like a book. When there is a space in the middle, just jump across it as if you were reading around a picture inserted in the text on a page. When you read a page in a book from left to right, you have to drop down a line to continue. The same is true for the periodic table. There is something very exciting happening when you move down on the table to a new line. You are moving to a row of elements with another energy level for the atoms' electrons to fill. This means that the top row has only one energy level. The second row (period) adds a level to have a total of two energy levels that the electrons must fill. The third period contains three energy levels for electrons, and so on. The most energy levels currently found in an atom of an element at this time is seven. We have seven periods in the periodic table (the two bottom rows are actually continuations of the 6th and 7th periods.) The period number is usually found to the left of the first element box for each row.

Illustration of periods