2.  ALL chemicals can be classified as either ELEMENTS or COMPOUNDS.

3.  Elements are SUBSTANCES THAT CANNOT BE BROKEN DOWN DURING A CHEMICAL REACTION. Examples include: H, O, Na, C, etc.  There are 91 naturally occurring elements-others are artificially created.

4.  Compounds are: SUBSTANCES THAT COULD BE BROKEN DOWN INTO ELEMENTS DURING A CHEMICAL REACTION. Examples include: H2O, NaCl, CO2, etc.

5.  A POLYMER is a chemical compound formed by the union of small molecules and usually consisting of repeating structural units. Examples include: silly putty, Flubber, Oobleck, and bouncy balls.

6.  In 1869 a Russian chemist named Dimitri Mendeleev announced that he had developed a chart of the elements. He listed the elements by increasing atomic mass. His chart was called the periodic table.  Today, the elements are listed by increasing atomic number.

7.  Elements are organized according to chemical properties. Elements with similar properties are listed in columns, vertically (up/down). These are called groups or families. There are 18 from left to right. The noble gases, alkali metals, and halogens are examples.

8.  The rows or horizontal lines of elements are called periods. There are 7 of these.  On the right side of the table is a zig-zag line. It is the boundary between the metals and nonmetals.

9.  The metals that are found to the left of the zigzag are good conductors of heat and electricity, can be hammered into different shapes, and are shiny. All metals are solids at room temperature except Mercury.

10.  The non-metals are found to the right of the zigzag. They are poor conductors of heat and electricity, are brittle and do not shine.

11.  Each box on the table represents an element. It contains the atomic number, the name, the symbol, and the atomic mass.  Draw and label this element box: