1. Ionic Compound Formulation & Nomenclature

2. • All ionic compounds consist of two parts: a cation (a positive ion) and an anion (a negative ion).
• Ions are combined in simple, whole-number ratios to balance their charges. This results in a net charge of zero, which all ionic compounds MUST have.
• The “cross technique” is used to create the correct ratio of ions needed.
Example: aluminum (Al+3) and oxygen (O-2).
Al O
Al O
Al O
2 3
1. Write the symbols, then write the charges on each symbol (from ion list)
2. Cross the charges, dropping the + and – symbols
(don’t write 1s)
3. Clean up the formula (completely erase all charges) and reduce if necessary.
So when do you need to reduce?

3. Ca O Ca O CaO Sn S Sn S SnS2 +2 -2 2 2 +4 -2 2 4 2
• Here’s two examples of when the ratio needs to be reduced:
Ca O
Ca O
CaO
2 2
Sn S
Sn S
SnS2
2 4 2
• Let’s try formulating some compounds (putting them together):

4. Mg+2 F- Fe+3 Br- K+ Cl- Ca+2 Cl- Ag+ N-3 MONATOMIC
• Let’s try formulating some compounds (putting them together):
Let’s try naming some compounds:
MONATOMIC
magnesium fluoride = ______________
iron (III) bromide = ________________
potassium chloride = ______________
calcium chloride = ________________
silver nitride = ____________________
MgF2
FeBr3
KCl
CaCl2
Ag3N
tin (II) sulfide = ___________________
barium phosphide = _______________
cobalt (III) oxide = _________________
copper (I) iodide = _________________
lead (IV) selenide= ________________
Mg+2 F-
Fe+3
Br- K+
Cl-
FeO ___________________
Al2O3 __________________
K2O____________________
PbO2 __________________
K2S ___________________
Mn3P2 ___________________
Na2S____________________
Ag2S ____________________
Cu3N ____________________
ZnCl2 ___________________
Ca+2
Cl-
Ag+
N-3

5. Sn+2 S-2 Ba+2 P-3 Co+3 O-2 Cu+ I- Pb+4 Se-2 MONATOMIC
• Let’s try formulating some compounds (putting them together):
Let’s try naming some compounds:
MONATOMIC
magnesium fluoride = ______________
iron (III) bromide = ________________
potassium chloride = ______________
calcium chloride = ________________
silver nitride = ____________________
MgF2
FeBr3
KCl
CaCl2
Ag3N
tin (II) sulfide = ___________________
barium phosphide = _______________
cobalt (III) oxide = _________________
copper (I) iodide = _________________
lead (IV) selenide= ________________
Sn2S2
Ba3P2
Co2O3
CuI
Pb2Se4
SnS
PbSe2
Sn+2
S-2
Ba+2
P-3
Co+3
O-2
FeO ___________________
Al2O3 __________________
K2O____________________
PbO2 __________________
K2S ___________________
Mn3P2 ___________________
Na2S____________________
Ag2S ____________________
Cu3N ____________________
ZnCl2 ___________________
Cu+ I-
Pb+4
Se-2

6. Zn+2 = zinc Fe+2 = iron (II) Sc+3 = scandium Fe+3 = iron (III)
• Ionic compounds are named with the following rules:
• The cation name goes first, the anion name goes second.
• cations are usually metals. The name of the cation does
not change from the name of the element.
• Note: If the element is polyionic (meaning it can have more than
one type of charge), this must be indicated by placing a roman
numeral after the name to indicate the size of the charge.
• anions are a single negatively charged element
(monatomic)—name of element with ending taken off and
“-ide” added.
Zn+2 = zinc
Sc+3 = scandium
Fe+2 = iron (II)
Fe+3 = iron (III)

7. iron ( ) oxide aluminum oxide potassium oxide lead ( ) oxide
• Let’s try formulating some compounds (putting them together):
Let’s try naming some compounds:
magnesium fluoride = ______________
iron (III) bromide = ________________
potassium chloride = ______________
calcium chloride = ________________
silver nitride = ____________________
MgF2
FeBr3
KCl
CaCl2
Ag3N
tin (II) sulfide = ___________________
barium phosphide = _______________
cobalt (III) oxide = _________________
copper (I) iodide = _________________
lead (IV) selenide= ________________
Sn2S2
Ba3P2
Co2O3
CuI
Pb2Se4
SnS
PbSe2
iron ( ) oxide
aluminum oxide
potassium oxide
lead ( ) oxide
potassium sulfide II IV
manganese ( ) phosphide
sodium sulfide
silver sulfide
copper ( ) nitride
zinc chloride II I
FeO ___________________
Al2O3 __________________
K2O____________________
PbO2 __________________
K2S ___________________
Mn3P2 ___________________
Na2S____________________
Ag2S ____________________
Cu3N ____________________
ZnCl2 ___________________

8. Covalent Bonding Characteristics and Nomenclature

9. Covalent compounds share electrons, (ionic bonds transfer them).
Covalent bonds = two nonmetals, or a nonmetal and a metalloid.
Remember, hydrogen is not an alkali metal, it is a nonmetal.
Remember, ionic bonds always contain a metal. Metals never appear in covalent compounds!!!
Covalent bonds rely on the “octet rule,” meaning that atoms in a covalent bond need 8 electrons around them (in most cases).
covalent bonds can be single, double, or triple, in order to satisfy the octet rule.
Lewis-dot structures show the arrangement of these eight electrons
CF4
CO2 N2
4 single bonds
2 double bonds
1 triple bond F
F C F O C O N N

10. covalent compounds can involve the same elements with multiple ratios (such as C3H8, C2H4, NO2, N2O), so the ratio in the compound must be shown in the name.
to write the name of a covalent compound, we use Greek prefixes:
attach the appropriate prefix to the name of each element in the compound. (Note: if the first element in the compound is single, you do not need the prefix “mono-.” “Mono-” is only used on the second element!)
the ending of the second element’s name is taken off, and “-ide” is added.
if you get any of the following vowel combinations in the name when you add the prefix: “oo,” “ao,” “oa,” or “aa,” that’s not allowed! Drop the vowel off of the prefix, and then add it to the name.
for diatomic gases, like O2, name the element, then add the word “gas.” Therefore, O2 = oxygen gas #
Prefix 1
mono- 2
di- 3
tri- 4
tetra- 5
penta- 6
hexa- 7
hepta- 8
octa- 9
nona- 10
deca-

11. dicarbon hexanitride no AO combo! triphosphorus heptaoxide heptoxide
Let’s try a few:
C2N6 = _____________________
P3O7 = _____________________
H2O = ______________________
B5As = ______________________
N2 = _______________________
trisulfur tetrachloride = ___________
carbon monoxide = ___________
chlorine gas = ____________
silicon pentabromide = ___________
tetrachlorine decabromide = ___________
dicarbon
hexanitride
no AO combo!
triphosphorus
heptaoxide
heptoxide
no OO combo!
dihydrogen
monoxide
monooxide
no OA combo!
pentaboron
monoarsenide
monarsenide
nitrogen gas
(diatomic gas!) S3
Cl4 C O
Cl2
(diatomic gas!) Si
Br5
Cl4
Br10

12. Place an “I” or a “C” in the blank:
Can you tell the difference between an ionic compound and a covalent compound based on the name or formula alone? You need to be able to do so!
Place an “I” or a “C” in the blank:
Fe3N2
K2S
NH3
Br2
Mn2O3
CaO
Li2O
___ I
___ C
carbon dioxide
aluminum nitride
tin (II) sulfide
chlorine gas
calcium sulfide
cobalt (III) oxide
sodium phosphide I I C I C C I I I I I I