ELEMENTS

3. PURE SUBSTANCE
Something that can not be broken
down into simpler matter using
physical methods.
There are two types of substances…
Elements & Compounds.

4. ELEMENTS
 Are the simplest kind of
pure substance.
 There are ~ 110 elements,
each made of a different type
of atom (periodic table).

5.  Each element has a name and symbol.

6. Each has a unique set of
properties
• Called characteristic
properties
• Can be physical or
chemical
Classified by their
properties
1. Metals
2. Nonmetals
3. Metalloids Elements
Metals
Nonmetals
Metalloids

7. METALS
•Shiny
•Good
conductors
•Malleable
•Ductile
•Ex: gold,
silver, copper
NONMETALS
•Dull (no shine)
•Poor conductors
•At room temp,
only a few are
solids that are
brittle
•Most are gases
•Ex: hydrogen,
oxygen, helium
METALLOIDS
•Characteristics
of metals and
nonmetals
•Semiconductor
s
•Ex: silicon,
germanium

8. COMPOUNDS
 Are pure substances that are
composed of multiple types of
elements (2 or more),
chemically bonded to one
another.
 Compounds can not be
broken down by physical
methods (they can be broken
down by chemical reactions).

9. • Do you know any compounds?
• How are they different from elements?
• Characteristics
1. Found in nature more often than pure elements
2. Have more than one element
3. Elements are chemically bonded to each other
– Mg + O2 makes MgO
4. Pure substances that occur in fixed ratios by mass
– 1g H to 8g of O in every water molecule
5. Can’t be separated by physical means
6. Have their own unique set of properties

10. CLASSIFICATION OF MATTER