Chapter 2 - Atoms and Molecules
Atoms
-
build molecules
-
composed of subatomic particles
-
protons
-
electrons
-
neutrons
- atomic number
-
# protons = # electrons
-
# neutrons varies
-
energy levels
-
elements
-
composed of a specific type of atom
-
have a unique atomic number
-
have unique characteristics
Molecules
-
atoms held together by chemical bonds
-
full shells give stability
-
chemical bonds
-
ionic bonds (attraction of ions)
-
covalent bonds (atoms share electrons)
© Carol L. Wymer, 2003