Untitled - Kelly Walsh High School

18 CHEMISTRY FOR THE UTTERLY CONFUSED
Careful!
Quick Tip
stair-stepped line starting at boron (B) and moving down and to the right. The
elements bordering this line (B, Si, Ge, As, Sb, Te, At) are the metalloids.
These metalloids have properties of both of the other two groups (metals and
nonmetals). They have unusual electrical properties that make them valuable in
the computer and semiconductor industry.
We classify the elements to the left of this line, excluding the metalloids and
hydrogen, as the metals. The metals have physical properties that we normally
associate with metals in the everyday world––they are solids (with the exception
of mercury), they have a metallic luster, and are good conductors of both
electricity and heat. They are malleable (capable of being hammered into thin
sheets) and ductile (capable of being drawn into thin wires). And as we will see
later in this book, the metals tend to lose electrons in chemical reactions.
Even though hydrogen is located on the left side of the periodic table, it is a
nonmetal.
The other elements, the ones to the right of the line and metalloids and also
including hydrogen are classified as the nonmetals. The nonmetals have properties
that are opposite of the metals. Many are not solid, they have a dull luster,
are nonconductors, and are neither malleable nor ductile. The nonmetals
tend to gain electrons in chemical reactions.
You should highlight or color the metalloid elements on the periodic table for
practice to help you locate the metals and nonmetals. Left = Metals; Right =
Nonmetals.
Another way of classifying the elements on the periodic table is by the period
and group to which they belong. Periods are the horizontal rows on the periodic