elements and compounds

1. Elements
Substance that contains only one kind of atom

2. Compounds
-Are substances made of atoms of two or more elements
that are chemically combined.
-The chemical formula of a compound shows the elements
that are in it
-Example:
SiO₂ (sand): It is formed of 1 Silicon atom
2 oxygen atoms

3. -Compounds don’t have the same properties of the
elements forming them
Example:
The ordinary table salt is a compound called NaCl
It is formed of :
1 atom of Sodium and 1 atom of chlorine
Where “Sodium” is a metal

4. • And “Chlorine” is a gas
But when they combine together they give a product of
different properties which is the table salt

5. How compounds are formed ?
-Compounds hold together because atoms bond or
attach to one another

6. How atoms can attach or bond with
each other?
They either
Share
electrons
Gain
Or
lose
electrons