Atoms form ions through gaining or losing electrons to achieve stable electron configurations. Oppositely charged ions attract and bond ionically, forming ionic compounds. Ionic compounds are named by listing the metal first followed by the nonmetal with an "-ide" ending. Transition metals require indicating their ionic state with Roman numerals. Polyatomic ions, like sulfate and nitrate, are also present in ionic compounds and identified by non-"-ide" endings. Covalent compounds form between nonmetals which share electrons in a covalent bond.

2.  Atoms gain or lose electrons to get a stable electron configuration.
 When this happens they become ions( charged atoms).
 Unlike charges attract so positive metal atoms(cations) attract and combine
with negative non-metal atoms(anions).
 When they combine they form a bond between the molecule(ionic bond).
Determining Factors:
1. Write symbols for elements
2. Write down charge of ion
3. “Cross over” charges
4. Reduce if possible
Ex. Lithium Sulphur
Li S
1+ 2-
Li2 S1
Li2S

3. Naming:
 Metal listed first
 Non-metal second
 Non-metal ending to “ide”
Transitions Metals:
 Metals that are in Group 3 or higher( including metalloids)
 Due to the complex electron configuration they can find multiple stable states.
 The only way to know the state is to indicate it. This is done with roman numerals
indicating ionic state.
 When naming transition metal compounds we need to indicate the ionic state. So
we need to figure it out.
Ex. Copper can be a one or a two.
Copper(2) Chloride
Cu Cl
2+ 1-
CuCl2

4. Poly- many
Polyatomic Ions- ions made up of many ions
 Some combinations of atoms provide stability, but result in an overall charge.
 To balance the charge they combine with other ions resulting in a neutral molecule.
 Polyatomic ions “travel” as a group, indicated by placing them in brackets, When
there is more than one in a molecule.
Ex. NO3
SO4
ClO3
 You will know that an ionic compound contains a polyatomic ion, when the name
doesn’t end in “ide”.
 Anytime you see a non “ide” ending you looking for the polyatomic ion.
 The only “metal” polyatomic ion is Ammonium (NH4+).

5. Co- together
Valent- outer orbit
Covalent- share outer orbit
 This type of bond occurs between two or more Non-metal atoms.
 In covalent bonding the electrons are not exchanged, they are shared.
Ionic Covalent
 Metal to non-metal Non-metal to non-metal
 Gain or lose electrons sharing electrons
 Full outer orbit shared outer orbit
 Specific ratios multiple possible ratios
 Roman numerals for transition metals Latin prefixes on all compounds

6. 1. mono 6. hexa
2. Di 7. nepta
3. Tri 8. octa
4. Tetra 9. hona
5. Penta 10. deca
Count number of elements
When using tetra and penta in front of oxide, drop the
“a”.

7. Notes
Text book
Mr. Baker