Molecules: Elements vs. Compounds
Apply the information from the reading passage to fill in the missing parts on the
table.
Molecules are classified into two major types: elements and compounds. If a molecule is made out of
only one type of atom, it is an element. Molecules that have more than one type of atom are called
compounds. All molecules are made of atoms that have been joined together. If all of the atoms in a
molecule are alike, then the molecule is classified as an element. However, if all of the atoms are not the
same, the molecule is classified as a compound. Therefore, the O2 we breathe is an element since both of the
atoms are oxygen. The aspirin molecule of C9H8O4 is made of three different types of atoms: carbon atoms,
hydrogen atoms, and oxygen atoms. Therefore, C9H8O4 is a compound. Bonding involves two or more
elements coming together. Ionic bonds are between metal and a nonmetal or between metals. Covalent
bonds are between nonmetals.
Formula of
Molecule
H2O
NO
CI2
AgNO3
ZnC4H4O6
AlPO4
O2
KH
Br2
NiF2
C7H4BrNO4
C9H8O4
F l2
CO2
C6H12O6
H2O2
O3
# of atoms in molecule and elements
2- hydrogen and oxygen
Classification:
Element or
Compound
compound
Type of Bond:
Ionic or Covalent
Covalent