Chemistry 11 – Unit #1
Nomenclature
Binary Compounds with Elements having one valence (charge) value
 Binary compounds contain two elements only.
 They are usually ionic compounds
 When naming compounds the least electronegative element is usually written first.
Rules for Binary Compounds



The name of the binary compound always ends in "ide".
The first mentioned element uses its name as it appears on the Periodic table
Elements have a valence value determined by their group on the Periodic table
1+
2+
3+
4 +/-
3-
2-
1-
0
N.B. see the periodic table for valences of the transitions metals
Zero Sum Rule: For neutral chemical formulas containing ions, the sum of the positive
and negative ions must equal zero.
Cross-over-rule for writing Formulas
1. Write down the symbols of the elements in the order given in the name
2. Write valences above elements symbol
3. Divide valences by the highest common multiple
4. Cross-over valences
5. Drop all 1's and unnecessary brackets
Examples:
sodium oxide Na2O
calcium sulfide CaS
magnesium bromide MgBr2
Exercise:
For all exercises you will give the name if formula provided and the formula if the name is provided.
1) calcium nitride
_______
8) silicon oxide
_______
2) aluminum carbide
_______
9) aluminum bromide
_______
3) silver sulphide
_______
10) zinc oxide
_______
4) sodium fluoride
_______
11) potassium bromide
_______
5) barium iodide
_______
12) magnesium chloride
_______
6) LiCl ___________________________
13) BaO __________________________________
7) K2S______________________________
14) Al2O3 _________________________________
Binary Compounds with Elements having multiple valence values
Rules for Binary Compounds


The name of the binary compound always ends in "ide".
Whenever the first mentioned element has more than one valence value, this must be indicated in
the name. It will always be the first element. The second element has a valence value equal to the
value for its group on the periodic table.
Certain valence values of transition metals must be memorized.
On the Periodic table, above each symbol are a number of values which the legend calls
oxidation states. In many cases these also correspond to valence values.
There are three ways of naming compounds containing elements that can have multiple valences,
The different methods must not be mixed.
Method 1 - Roman numeral method (IUPAC)
 The valence value to be used is indicated by using uncrossed Roman numerals
 It is placed in brackets immediately following the name of the first element.
Examples:
iron(III) chloride
nickle (III) sulfide
FeCl3
Ni2S3
tin(IV) iodide
mercury(II) oxide
SnI4
HgO
Exercise:
For all exercises you will give the name if formula provided and the formula if the name is provided.
1) iron(III) chloride
________
12) copper(II) sulphide
________
2) tin(IV) oxide
________
13) arsenic(V) iodide
________
3) phosphorus(V) chloride ________
14) gold(I) fluoride
________
4) copper(I) bromide
15) sulphur(VI) oxide
________
________
5) antimony(V) sulphide ________
16) bismuth(v) phosphide ________
6) arsenic(III) oxide
________
17) mercury(II) chloride
________
7) mercury(I) sulphide
________
18) gold(III) chloride
________
8) Pb3N2
_________________________
19) SbF3
____________________________
9) NiI2
_________________________
20) MnO2
10) Co2Se3
_________________________
21) BiF5
_____________________________
11) SnO2
_________________________
22) ZnO
_____________________________
____________________________
Method 2 - "ous' and "ic" method
 When the first written element has two valences only, the name of the element ending with "ous"
denotes the lower valence value
 The name of the element ending with an "ic" denotes the higher valence values.
1. In some cases, the latin name for the element is used:
iron:
gold:
copper:
tin:
lead:
cobalt
nickel
mercury
platinum
ferrous
aurous
cuprous
stannous
plumbous
cobaltous
nickelous
mercurous
platinous
(valence = 2+)
(valence = 1+)
(valence = 1+)
(valence = 2+)
(valence = 2+)
(valence = 2+)
(valence = 2+)
(valence = 1+)
(valence = 2+)
and
and
and
and
and
and
and
and
and
ferric
auric
cupric
stannic
plumbic
cobaltic
nickelic
mercuric
platonic
(valence = 3+)
(valence = 3+)
(valence = 2+)
(valence = 4+)
(valence = 4+)
(valence = 3+)
(valence = 3+)
(valence = 2+)
(valence = 4+)
2. Some elements having more than two valence values or oxidation states use specific values for
the "ous" and the "ic".
nitrogen
manganese
bismuth
ous = 1- ic = 2ous = 2+ ic = 3+
ous = 3+ ic = 5+
chromium
phosphorus
arsenic
ous = 2+ ic = 3+
ous = 3- ic = 5ous = 3+ ic = 5+
Examples:
stannous chloride
SnCl2
phosphorous oxide
P 2 O3
manganous fluoride
MnF2
nitric oxide
NO
Exercise:
For all exercises you will give the name if formula provided and the formula if the name is provided.
1) ferric oxide
_________________
11) stannic oxide
_________________
2) phosphoric sulfide
_________________
12) arsenous nitride
_________________
3) cuprous fluoride
_________________
13) nickelous fluoride
_________________
4) stannic fluoride
_________________
14) cuprous nitride
_________________
5) antimonous sulfide
_________________
15) auric chloride
_________________
6) cupric bromide
_________________
16) cupric sulfide
_________________
7) NiI2
_________________
17) Pt02
_________________
8) HgBr
_________________
18) As4C5
_________________
9) CoCl3
_________________
19) Au2S
_________________
10) As3N5
_________________
20) PbCl4
_________________
Method 3 - Greek prefix method
 This method does not use the valence values.
 The Greek prefix is placed in front of the element name to indicate how many atoms
of the element to place in the formula.
 The word "mono" is usually omitted only if it applies to the first element.
Prefixes:
mono = 1
hexa = 6
di = 2
hepta = 7
Examples:
diphosphorus pentoxide
carbon monoxide
tri =3
octa = 8
tetra = 4
nona = 9
penta = 5
deca = 10
P 2 O5
CO
arsenic trichloride
xenon tetrafluoride
AsCl3
XeF4
Exercise:
For all exercises you will give the name if formula provided and the formula if the name is provided.
1) xenon hexafluoride
_________________
12) sulfur dioxide
_________________
2) sulphur trioxide
_________________
13) carbon dioxide
_________________
3) carbon disulphide
________________
14) diphosphorus trisulfide
_________________
4) silicon dioxide
_________________
15) silicon tetrachloride
_________________
5) lead dioxide
_________________
16) manganese dioxide
_________________
6) nitrogen dioxide
_________________
17) nitrogen tetroxide
_________________
7) carbon tetrachloride
_________________
18) lead dioxide
_________________
8) dichlorine monoxide
_________________
19) diphosphorus pentasulphide
________________
9) KrF2
______________________
20) ICl
______________________
10) SeCl2
______________________
21) ICl7
______________________
11) NF3
______________________
22) P2S5
______________________
Formula of elements:
 Most elements are written as single entities:
 Metals (solids in their standard state except mercury)
 Noble gases
 Diatomics - H O F Br I N Cl (all are gasses except Br and I)
Eg: hydrogen H2(g); oxygen

O2(g) ; nitrogen N2(g); bromine Br2(l) ; iodine I2(s)
two other non-metals exceptions: sulphur S(s) & S8(s) ; phosphorus P(s) & P4(s)
Polyatomic ions (Radicals)
 Is an ion made up of two or more atoms
 Some of the following list of polyatomic ions will have to be memorized along with their valences.
 These polyatomic ions behave as if they were a single entity and follow the cross-over rule in the
same manner as other single elements.
 Brackets are used in the formula, only if it turns out that there are 2 or more of the polyatomic ion
indicated in the formula: Eg. Brackets are used in Al2(SO4)3 but not in Na3PO4
 The only polyatomic cation to be studied is NH4+
 The others are polyatomic anions. i.e. they carry a negative charge
See p. 666 to fill in table
radical name
formula
radical name
thiocyanate
SCN-
nitrate
cyanide
formula
nitrite
-
cyanate
CNO
carbonate
hypochlorite
thiosulfate
chlorite
sulfate
chlorate
sulfite
perchlorate
phosphate
hydroxide
ammonium
N.B. see p. 666 in text for other common polyatomics.
“Nick
the
__________
Camel had a Clam
__________
for Supper
in
Phoenix.”
__________
__________
_________
calcium hydroxide
Ca(OH)2
iron (II) nitrite
magnesium cyanide
Mg(CN)2
ammonium hydroxide
sodium phosphate
Na3PO4
sodium hypochlorite
Examples:
Fe(NO2)2
NH4OH
NaClO
1) potassium hydroxide
__________________
11) iron(III) cyanate
__________________
2) barium hydroxide
__________________
12) ammonium chloride
__________________
3) copper(II) sulphate
__________________
13) ammonium dichromate __________________
4) ammonium bromate
__________________
14) ferrous hydroxide
__________________
5) nickel(III) cyanide
__________________
15) auric bromide
__________________
6) cobalt(II) cyanate
__________________
16) zinc hydroxide
__________________
7) gallium dichromate
__________________
17) potassium chromate
__________________
8) Sn(CN)4
______________________
18) Al(OH)3
______________________
9) KMnO4
_______________________
19) CsCN
_______________________
10) Cu(NO3)2
_______________________
20) Ca(SCN)2
_______________________
Hydrates:
Greek prefixes are used to indicate how many water molecules are associated with the crystal.
Examples:
CuSO4.5H2O
Cl2.8H2O
copper(II) sulfate pentahydrate
chlorine octahydrate
1) calcium sulfate dihydrate
__________
10) cobalt(II) perchlorate pentahydrate__________
2) magnesium sulfite heptahydrate __________
11) barium chloride dihydrate
__________
3) sodium carbonate decahydrate
_________
12) aluminum nitrate monohydrate
__________
4) aluminum oxide monohydrate
__________
13) bromine decahydrate
__________
5) ferric chloride hexahydrate
__________
14) iodine tetrahydrate
__________
6) calcium nitrate trihydrate
__________
15) copper(II) sulfite hexahydrate
__________
7)cadmium bromide tetrahydrate
__________
16) ferrous iodide tetrahydrate
__________
8) chromium(III) nitrate nonahydrate_________
17) lithium chloride monohydrate
__________
9) barium hydroxide octahydrate
18) beryllium nitrate tetrahydrate
__________
__________
Peroxides:
These are binary oxides, which contain an extra oxygen atom. (O22- = peroxide radical)
Rule:
1. Write the formula as if the regular oxide
2. Add on one extra oxygen atom
Na2O
Na2O2
H2O
H2O2
CaO
CaO2
Do not at this stage cancel any of the subscripts.
1) zinc peroxide
____________________
6) potassium peroxide
____________________
2) calcium peroxide
____________________
7) strontium peroxide
____________________
3) cesium peroxide
____________________
8) hydrogen peroxide
____________________
4) copper(II) peroxide
____________________
9) barium peroxide
____________________
5) magnesium peroxide
____________________
10) aluminum peroxide ____________________
Thio Compounds
The prefix thio in the name indicates that an oxygen atom has been replaced by a sulphur atom.
Examples:
potassium sulphate
K2SO4
potassium thiosulphate
K2S2O3
sodium carbonate
Na2CO3
sodium thiocarbonate
Na2SCO2
potassium cyanate
KCNO
potassium thiocyanate
KSCN
1) ammonium thiocyanate ___________________
4) potassium thiosulfate
2) sodium monohydrogenthiosulphate ___________
5) aluminum thiocarbonate __________________
3) CaS2O2
6) AlSPO3
_________________________
___________________
_________________________
NOMENCLATURE 4
ACIDS:
There are three groups of acids:
- binary acids
- oxy acids
- derived oxy acids
Binary Acids
1. All have the prefix hydro and end with ic.
2. All must contain hydrogen as the first element.
3. Use the normal cross-over-rule to determine the formula.
4. All are dissociated in water and must be so indicated by using (aq) behind the formula.
5. Have no oxygen in their formula
Examples:
hydrochloric acid
HCl(aq)
hydrosulfuric acid
H2S(aq)
hydrocyanic acid
HCN(aq)
Exercise:
For all exercises you will give the name if formula provided and the formula if the name is provided.
hydrobromic acid
________
hydroselenic acid
________
hydroiodic acid
________
hydrophosphoric acid
________
hydrofluoric acid
________
hydrofluoric acid
________
hydrotelluric acid
________
hydrosulfuric acid
________
Oxy acids
1. All contain H, O and at least one other non-metal element
2. The name of the acid ends in ic.
3. The name of the associated radical ends in ate.
4. The valence value of the associated radical is equal to the number of acidic hydrogen atoms in
the acid.
The following six oxy acids and their associated radicals along with their valence values must be memorized:
Name of the Acid
Formula of the Acid
Name of the
Formula of the
valence value for the
associated radical
associated radical
associated radical
chromic acid
H2CrO4
chromate
CrO4
2
nitric acid
HNO3
nitrate
NO3
1
fluoric acid
HFO3
fluorate
FO3
1
carbonic acid
H2CO3
carbonate
CO3
2
sulfuric acid
H2SO4
sulfate
SO4
2
phosphoric acid
H3PO4
phosphate
PO4
3
NOTE:
Using the periodic table it is possible to write the names and formulas for a number of other oxy
acids using the fact that members of the same chemical family have similar chemical properties.
Elements of the same chemical family (group) follow the pattern of the oxy acid immediately above
the oxy acid that has been memorized.
Example: memorized acid = HFO3 Fluoric acid
therefore: HClO3 - Chloric acid
HIO3 - iodic acid
and HBrO3 - bromic acid.
Exercise: On a separate piece of paper complete the following chart for the acids listed.
Name of the acid
bromic acid
manganic acid
Formula of the acid
telluric acid
selenic acid
Name of the
Formula of the
Valence value of the
associated radical
associated radical
associated radical
dichromic acid
iodic acid
silicic acid
chromic acid
cyanic acid
arsenic
cid
NOMENCLATURE 5
Salts
 Salts are compounds which can be formed when an acid and a base neutralize each other.
 Most of the compounds in the section on binary compounds could be considered to be salts fromed
from a base and a binary acid.
 Salts can also be formed from a base and an oxy acid or derived oxy acid.
Examples:
sodium sulphate
Na2SO4
calcium phosphate
Ca3(PO4)2
aluminum carbonate
Al2(CO3)3
zinc perchlorate
Zn(ClO4)2
cupric nitrite
Cu(NO2)2
stannous hypoiodite
Sn(IO)2
Acid Radicals
 The oxy acids which have more than one acidic hydrogen are able to lose the hydrogens,
one at a time.
 This gives rise to radicals, with acidic hydrogens still attached
 These radicals are referred to as acid radicals:
H3PO4
H2PO 4
2-
H2PO 4-
___> H1+ + H PO 422
___> H1+ + HPO4___> H1+ +
PO 43-
Radical
Name
Valence value
PO4
HPO4
H2PO4
phosphate
monohydrogen phosphate
dihydrogen phosphate
3
2
1
* Valence value = Valence of the non-acid radical - # H's still attached.
For the following give the formula and valence value of the radicals listed:
phosphite
_____________ ____
monohydrogensulphate
________
____
monohydrogenphosphite
___________
suphite
________
____
dihydrogenphosphite
_____________ ____
monohydrogensulphite
________
____
hypophosphite
_____________ ____
carbonate
________
____
____
monohydrogenhypophosphite________
____
monohydrogencarbonate ________
____
dihydrogenhypophosphite ________
____
chromate
________
____
sulphate
____
monohydrogechromate
________
____
________
Acid Salts:
The acid radicals are treated just like any other radical:
Examples:
calcium dihydrogenhypophosphite
Ca(H2PO2)2
potassium monohydrogen carbonate
Aluminum hydrogensulphite
KHCO3
Al(HSO3)3
Note: mono is understood
Note: In some old texts, the prefix "bi" is sometimes used instead of monohydrogen. Its use is very selective and should not
be considered to name compounds, but know how to write the formulas when the prefix "bi" is used.
Examples:
sodium bicarbonate
NaHCO3
potassium bisulphite
KHSO3
sodium monohydrogenphosphate
___________
ferric monohydrogensulphate
____________
magnesium dihydrogenphosphat
___________
ammonium hydrogencarbonate
____________
aluminum dihydrogenphosphite
___________
chromium(III) hydrogensulphite
____________
chromium(III) hydrogenphosphite ___________
nickel(II) monohydrogensilicate
____________
cupric monohydrogenarsenate
___________
cadmium monohydrogenselenate
____________
stannic dihydrogenhypophosphite ___________
potassium monohydrogenselenite
____________
K2HPO3
Ba(HSO3)2
_________________________
_________________________
Bi2(HPO3)5
Pb(H 2PO2)2
_________________________
________________________
NOMENCLATURE 6
Derived Oxy acid and Salts worksheet
Exercise:
Complete the following table for the acids listed on a separate piece of paper.
phosphorous acid
bromic acid
iodous acid
hypophosphorous acid
bromous acid
hypoiodous acid
phosphoric acid
hypobromous acid
selenic acid
sulfuric acid
periodic acid
selenous acid
sulfurous acid
iodic acid
telluric acid
nitric acid
perbromicacid
tellurous acid
Name of the acid
Formula of the acid
Name of the associated
Formula of the
Valence value of the
radical
associated radical
associated radical
(A) salts from oxy acids
potassium chlorate
____________________
sodium carbonate
__________________
sodium nitrate
____________________
ferric sulfate
__________________
gold(I) phosphate
__________________
magnesium chlorate
__________________
__________________
iron(III) acetate
____________________
aluminum silicate
____________________
ammonium nitrate
magnesium phosphate
____________________
K2CO3
______________________
aurous sulfate
____________________
Na3PO4
______________________
ammonium chlorate
____________________
Fe(ClO3)2
______________________
zinc nitrate
____________________
Al(C2H3O2)3
______________________
potassium acetate
____________________
Zn3(PO4)2
______________________
lithium chromate
____________________
(B) Salts from derived oxy acids
sodium perchlorate
__________________
aluminum chlorite
__________________
aluminum sulfite
_________________
nickel(III) hypochlorite
__________________
cobalt(III) chlorite
__________________
tin(IV) phosphite
__________________
tin(IV) hypochlorite
__________________
magnesium phosphite
__________________
sodium phosphite
__________________
copper(I) permanganate
__________________
aluminum nitrite
__________________
ammonium hypophosphite __________________
cobalt(II) hypophosphite __________________
mercuric perchlorate
__________________
stannic perchlorate
__________________
magnesium sulfite
__________________
sodium sulphite
__________________
cuprous chlorite
__________________
ammonium hypoiodite
__________________
Pt(ClO)4
_______________________
gold(III) chromate
__________________
Ag2O
_______________________
NH4CNO
______________________
Ga(BrO4)3
_______________________