Chemical Nomenclature Workbook
Binary Ionic Compounds (containing only main group elements)
Write names and formulas for the binary ionic compounds formed from the following pairs of elements.
bromine and magnesium
aluminum and oxygen
nitrogen and sodium
aluminum and chlorine
calcium and phosphorus
barium and sulfur
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Worksheet
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Binary Ionic Compounds Containing Transition Metal Elements
Write names and formulas, as appropriate, for the following binary ionic compounds, containing transition (and post transition) metals.
Stock Name
­ic / ­ous Name
Formula
cobalt(II) chloride
cuprous oxide
Fe2O3
tin(IV) sulfide
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Worksheet
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Polyatomic Ions
These consist of two or more atoms that are covalently bonded together (like in a molecule) but the group of atoms has a net positive or negative charge.
The only polyatomic cation commonly found in ionic compounds is the ammonium ion, NH4+.
There are many polyatomic anions, and many of these contain oxygen atoms. They are called "oxoanions" or "oxyanions". They are named according to what atom the oxygen atoms are bonded to. Multiple oxoanions containing the same element are differentiated by suffixes, and sometimes, prefixes also. In many (but not all) cases, the oxoanions of an element have the same charge as the monatomic anion of that element.
PO43­
PO33­
P3­
phosphate ion
phosphite ion
phosphide ion
NO3­
NO2­
N3­
SO42­
SO32­
S2­
sulfate ion
sulfite ion
sulfide ion
Other polyatomic ions you may encounter:
ClO4­
ClO3­
ClO2­
ClO­
Cl­
perchlorate ion
chlorate ion
chlorite ion
hypochlorite ion
chloride ion
CO32­
CrO42­
Cr2O72­
nitrate ion
nitrite ion
nitride ion (pattern fails)
carbonate ion
chromate ion
dichromate ion
A few polyatomic ions end with ­ide (confusing!)
OH­
CN­
O22­
hydroxide ion
cyanide ion
peroxide ion
Note that all oxoanions of the same element have the same charge ­­ even if the monatomic anion has a different charge from that of the oxoanions.
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Write formulas for the following ionic compounds. All of these contain polyatomic ions.
sodium sulfate
aluminum carbonate
calcium phosphate
strontium sulfite
ammonium sulfide
potassium nitrite
magnesium nitrate
aluminum phosphate
barium hypochlorite
calcium hydroxide
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Binary Molecular Compounds
The binary molecular compounds consist of two non­metal elements, or a metalloid element and a non­metal element. With the exception of hydrogen and oxygen, the usual rule is that the element nearer to the left side of the periodic table is listed first (in both the name and formula). If the two elements are in the same group (vertical column), the element nearer to the bottom of the group is listed first. The element that is listed last gets the ­ide ending. Greek prefixes are used to indicate the number of atoms of each element in the molecule. Mono­ is omitted on the first element but included on the second element.
Number
Greek Prefix
Prefixes seen in some other contexts
1
2
3
4
5
6
7
8
9
10
mono­
di­
tri­
tetra­
penta­
hexa­
hepta­
octa­
nona­
deca­
uni­
bi­
ter­
quad­
pri­
sec­
sex­
sep­
Trivia: Note that the last 4 months of the year seem to have numeric prefixes, but they don't correspond to the positions of these months on our current calendar.
SEPtember
OCTober
NOVember
DECember
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Write chemical names or formulas as appropriate
P4O10
iodine heptafluoride
CH4 (methane)
NH3 (ammonia)
dihydrogen monoxide (what is this?)
boron trifluoride
dinitrogen pentoxide
OF2
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ACIDS
Binary Acids:
Ternary Acids
These consist of hydrogen and certain non­metal or metalloid elements. I will not ask that you know which elements render binary acids when combined with hydrogen. I will only ask that you know how to name the compound as an acid if told that it is an acid.
The pattern: hydro__________ic acid
These consist of hydrogen combined with an oxoanion. If the anion ends with ­ate ion, the acid with end with ­ic acid. If the anion ends with ­ite ion, the acid will end with ­ous acid. The number of hydrogen atoms in the formula will be equal to the number of negative charges on the polyatomic anion.
Examples:
HF
HCl
HBr
HI
H2S
hydrofluoric acid
hydrochloric acid
hydrobromic acid
hydroiodic acid
hydrosulfuric acid
Examples:
H2SO4
H2SO3
HNO3
HNO2
sulfuric acid
sulfurous acid
nitric acid
nitrous acid
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Write names and formulas for acids, as appropriate
carbonic acid
H3PO4
chlorous acid
HMnO4
HBr
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Worksheet
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Acid Anions and Acid Salts
We saw that oxoacids are obtained by adding enough hydrogen (as the H+ ion) to neutralize all of the negative charge on an oxoanion, resulting in a neutral molecule.
What if you don't add enough hydrogen to neutralize all of the negative charge? Then you get an acid anion.
SO42­
sulfate ion
HSO4­
hydrogen sulfate ion
(bisulfate ion)
H2SO4
sulfuric acid
SO32­
sulfite ion
HSO3­
hydrogen sulfite ion
(bisulfite ion)
H2SO3
sulfurous acid
PO43­
phosphate ion
HPO42­
monohydrogen phosphate ion
(biphosphate ion)
H2PO4­
dihydrogen phosphate ion
H3PO4
phosphoric
acid
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Write formulas for the following acid salts
calcium dihydrogen phosphate
potassium bisulfide
magnesium hydrogen sulfite
barium biphosphate
sodium bicarbonate (baking soda)
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Worksheet
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Hydrated Salts
Sometimes, ionic compounds have water molecules incorporated as part of their crystal structure. For example, if you dissolve some ionic compounds in water, the solid that you recover after evaporating the water will be the hydrated form of the salt.
Hydrated salts are named by using a Greek prefix to indicate the number of water molecules, followed by the word hydrate. This is appended to the end of the salt's chemical name.
The formula of a hydrated salt is written by appending . nH2O to the end of the salt's "regular" formula, where n is the number of water molecules. Note that the formula of the salt itself and the H2O are separated by a raised dot, much like that used in multiplication. In this case, however, it does not mean multiplication. Rather, it means that the water is attached. The raised dot is used to separate two separate formulas that are in and of themselves, stable formulas. That is, both the salt and the water could each exist on their own, without the other.
Examples:
Na2CO3 . 10H2O
sodium carbonate decahydrate
CuSO4 . 5H2O
copper(II) sulfate pentahydrate
(cupric sulfate pentahydrate)
CoCl2 . 6H2O
cobalt(II) chloride hexahydrate
(cobaltous chloride hexahydrate)
FeCl3 . 3H2O
iron(III) chloride trihydrate
(ferric chloride trihydrate)
MgSO4 . 7H2O
magnesium heptahydrate
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