Using the Table

Yes It Really Is Useful…

The Low Down

• The horizontal rows (going across) are called periods.

• Each period also signals an increase in energy levels…

• Remember: How many electrons does it take to fill up the first energy level?

• That’s why only H and He are in the first period.

The High Up

• The vertical columns are called groups (or sometimes families)

• Some of the groups are given names, such as the Noble Gases for Group 18.

• In fact, groups are going to be able to tell us very quickly the number of valence electrons.

But what about the rest…

• One the table there is something called the Main Group Elements…

• The main groups are: 1, 2, 13, 14, 15, 16, 17, and 18.

• The second number of the group number, is the number of valence electrons.

What else can we see?

• The elements are also classified:

• Metals, Non-Metals, and Metalloids

• Metals make up most of the Table…

• Groups 3-12 (called the transition elements) are all metals, and so are many other elements.

Ok…Non-Metals

• Non-Metals make up the upper right hand side of the table

• Many of them are gaseous at room temperature

• All of the Noble gases are Non-Metals

So what is a Metalloid?

• Metalloids are in between the metals and the non-metals, and have properties of both…

• Metals will conduct electricity, non-metals won’t, and metalloids will a little bit.

• Many semi-conductors are metalloids.