Periodic Table

2.  A period is a row of elements
 Properties change gradually and predictably.

3.  There are 18 columns of elements
 Each column contains a group, or family, of
elements.
 A group contains elements that have similar
physical or chemical properties.

4.  Divided into sections
 Groups 1,2 and the elements in Groups 13-
18
 Include metals, metalloids, and nonmetals

5.  Groups 3-12
 All metals
 Inner transition elements are placed below
the main table. (Lanthanide and Actinide)
 Why are they called that?

6.  All metals are solids
 Most with high melting points
 Exception is mercury
 Has luster (ability to reflect light)
 Good conductor of heat and electricity
 Malleable (can be pressed into thin sheets)
 Ductile (can be drawn out into wires)
 Tend to lose electrons and form positive ions in
chemical reactions.

7.  Gases or brittle solids at room temperature
 Poor conductors of heat and electricity
 17
 Include many essential for life
› Carbon --phosphorus
› Sulfur --iodine
› Nitrogen
› Oxygen
 Tend to gain electrons and form negative ions in
chemical reactions.

8.  Nonmetal
 Depending on the element with which
hydrogen is reacting, hydrogen will form a
positive or a negative ion.
 When bonding with other nonmetals,
hydrogen forms a positive ion.
 When bonding with metals, hydrogen forms
a negative ion.

9.  An element that shares some properties with
metals and some with nonmetals.
 Also called semimetals

10.  The box
 Name of the element
 Atomic number
 Symbol
 Average atomic mass
 Naturally occurring elements include a logo that
tells solid, liquid, gas at room temp.
 All gases, except hydrogen, are on the right
side of table

11.  Elements that do not occur naturally have a
bulls eye. They are the synthetic elements.

12.  One letter or two letter
 Based on element name
 Sometimes symbols don’t match the names. In
those cases, symbols might come from Greek
and Latin names for elements
 Some are named for geographic locations
 New elements given a temporary name and
three letter symbol that relates to the atomic
number.