Download I - Holland Public Schools

UNIT V - NOMENCLATURE
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I. Introduction
* nomenclature - naming of substances
* chemical formula - a series of symbols and numbers used to represent a compound or element
- element or compound? how many atoms of each element?
1) CH4
2) Fe
3) NaCl
4) H2
compound
element
compound
element
1 C, 4 H’s
1 Fe
1 Na, 1 Cl
2 H’s
5) Fe2O3
6) Ba(OH)2
compound
compound
2 Fe’s, 3 O’s 1 Ba, 2 O’s, 2 H’s
* we will deal with 3 types of compounds:
- ionic - a positive ion (metal or ammonium) & a negative ion (nonmetal or polyatomic ion)
- molecular or covalent - 2 nonmetals
- acids - molecular substance beginning with hydrogen
II. Naming Ionic Compounds
A. Name  Formula - each name has 2 parts:
1) First word - metal or ammonium (NH4+1) - always a positive charge
Group I or II
Metals
lithium
sodium
magnesium
calcium
Li+1
Na+1
Mg+2
Ca+2
Transition
Metals
Transition Metals
w/ no Roman Numeral
SCAZ
Cu+1
Cu+2
Fe+2
Fe+3
copper(I)
copper(II)
iron(II)
iron(III)
Ag+1
Cd+2
Al+3
Zn+2
silver
cadmium
aluminum
zinc
2) Second word - nonmetal or polyatomic anion - always a negative charge
Nonmetals
fluoride
chloride
oxide
nitride
Polyatomic Ions
F-1
Cl-1
O-2
N-3
hydroxide
carbonate
phosphate
phosphite
OH-1
CO3-2
PO4-3
PO3-3
3) Process - balance the positive and negative ions by using subscripts
* when using polyatomic ions use parentheses if you need more than one
Teacher Examples
Name
1) sodium
chloride
2) magnesium
chloride
3) calcium nitrate
4) aluminum
sulfate
Formula
Na
+1
Name
-1
Cl
NaCl
Mg+2 Cl-1
MgCl2
Ca+2 NO3-1
Ca(NO3)2
Al+3 SO4-2
Al2(SO4)3
5) ammonium
nitrate
6) copper(II)
sulfate
7) iron(III)
oxide
8) silver
carbonate
Student Examples
Formula
+1
NH4 NO3
Name
-1
NH4NO3
Cu+2 SO4-2
CuSO4
Fe+3 O-2
Fe2O3
Ag+1 CO3-2
Ag2CO3
1) barium
bromide
2) sodium
sulfate
3) ammonium
carbonate
4) nickel (II)
chloride
Formula
Ba
+2
Br
-1
BaBr2
Na+1 SO4-2
Na2SO4
NH4+1 CO3-2
(NH4)2CO3
Ni+2 Cl-1
NiCl2
Name
Formula
5) lead (II)
hydroxide
Pb+2 OH-1
6) lead (IV)
hydroxide
7) aluminum
phosphate
8) mercury (II)
oxide
Pb(OH)2
Pb+4 OH-1
Pb(OH)4
Al+3 PO4-3
AlPO4
Hg+2 O-2
HgO
UNIT V - NOMENCLATURE
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B. Formula  Name - first element is a metal or ammonium
* process is reverse of part (A)
1) Binary Compounds - metal and nonmetal
a) representative metal - name metal and nonmetal (remember it ends with “-ide”)
T.
1) BaCl2
barium chloride
2) AlF3
aluminum fluoride
S.
1) K2O
potassium oxide
2) Al2S3
aluminum sulfide
b) transition metal - must find charge of metal and give it a roman numeral
T.
1) CuCl
copper(I) chloride
S.
* you know that chloride is -1, so
the copper must be +1 if compound
is neutral
1) FeCl2
iron(II) chloride
* you know that chloride is -1
so 2 chlorides have a total charge of -2;
iron must have a charge of +2
2) Cu2O
copper(I) oxide
2) Hg2O
* you know that oxide is -2, so the coppers
must, as a team have a +2 charge; dividing that
+2 by the 2 copper ions present makes the charge
on each copper +1
mercury(I) oxide
3) FeO
iron(II) oxide
3) Cr2O3
chromium(III) oxide
* 3 oxides at -2 = -6
+6 divided by 2 Cr’s = +3
4) Fe2O3
iron(III) oxide
4) SnCl4
tin(IV) chloride
2) Ternary - name metal and polyatomic anion (give metal roman numeral if needed)
* remember that all ionic compounds in this chapter have 2 words in the name
so the groups of atoms at the end must only have one word to describe them.
Look on the chart of polyatomic ions for their names.
T.
1) NaNO3
sodium nitrate
2) Fe(OH)3
S.
1) Ca(ClO3)2
calcium chlorate
iron(III) hydroxide
2) (NH4)2SO3
ammonium sulfite
3) (NH4)2SO4
ammonium sulfate
3) CuOH
copper(I) hydroxide
4) Al2(SO4)3
aluminum sulfate
4) Cu3(PO4)3
copper(II) phosphate
UNIT V - NOMENCLATURE
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III. Molecular Compounds - 2 nonmetals; no ions are present, therefore NO CHARGE BALANCING!!!
* always binary (no polyatomic ions)
* how do we know the number of each element present? we use prefixes:
Prefix Number Prefix Number
mono1
penta5
di2
hexa6
tri3
octo8
tetra4
deka10
A) First nonmetal
* name the element; use a prefix if there are 2 or more of that element; DON’T USE MONOB) Second nonmetal
* always use a prefix; use name of element with an ending of “-ide”
T.
S.
1) CO2
carbon dioxide
1) CCl4
carbon tetrachloride
2) CO
carbon monoxide
2) N2O5
dinitrogen pentoxide
3) N2O3
dinitrogen trioxide
3) P4O10
tetraphosphorus dekoxide
* now go in reverse:
S.
1) silicon dioxide
SiO2
4) disulfur trioxide
S2O3
2) nitrogen monoxide
NO
5) hexacarbon hexahydride
C6H6
3) xenon tetrafluoride
XeF4
6) phosphorus trichloride
PCl3
UNIT V - NOMENCLATURE
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IV. Naming Acids
* treated as an ionic compound with H+1 (hydrogen ion) as cation
* negative ion can be nonmetal (binary acid) or polyatomic anion (ternary acid)
A) Binary acids – acids that contain a negative ion ending in “-ide”
1) Formula  Name
* use prefix: hydro* use root of anion’s name
* use suffix: -ic
T.
HCl
hydrochloric acid
S. 1) HBr
hydrobromic acid
2) H2S
hydrosulfuric acid
2) Name  Formula
* follow above rules in reverse
* be sure to balance charges
T.
hydroiodic acid
HI
S. 1) hydrofluoric acid
HF
2) hydrocyanic acid
HCN
B) Ternary acids
* DO NOT BEGIN WITH “hydro-“!!!!!!!
* use name of polyatomic ion and switch its ending:
Ion Ending
Acid Name
-ide
hydro-____-ic acid
-ate
_______-ic acid
-ite
_______-ous acid
* NOTE: sulfur stays “sulfur-” + ending, phosphorus stays “phosphor-” + ending
1) Formula  Name
T.
S.
1) HClO3
chloric acid
1) HClO2
chlorous acid
2) H2SO3
sulfurous acid
2) H2SO4
sulfuric acid
2) Name  Formula
T.
S.
1) acetic acid
HC2H3O2
1) perchloric acid
HClO4
2) phosphoric acid
H3PO4
2) carbonic acid
H2CO3
3) nitric acid
HNO3
3) phosphorous acid
H3PO3
UNIT V - NOMENCLATURE
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Name  Formula
BINARY ACID
YES
Is the second
word “acid”?
YES
Does it begin
with “hydro-“?
NO
NO
Is the element
represented by the
first word a metal
or ammonium?
1) Use H+ as the cation.
2) Change the “-ic” ending to “-ide”
and find the ion and its charge.
3) Charge-balance the compound.
YES
TERNARY ACID
1) Use H+ as the cation.
2) If the first word ends in “-ic”, change it to “-ate”.
If the first word ends in “-ous”, change it to “-ite”.
Find the ion and its charge.
3) Charge-balance the compound.
IONIC COMPOUND
1) Find the formula and charge of the cation. If it is a metal, look
on the periodic table. If it is a transition metal, the roman
numeral represents its positive charge. Ammonium is NH4+.
2) Find the formula and charge of the anion. If it ends in “-ate” or
“-ite”, it is on the polyatomic ion sheet. If it ends in “-ide”, and
it is not on the polyatomic ion sheet, it is a nonmetal on the
periodic table.
3) Charge-balance the compound.
NO
MOLECULAR COMPOUND
1) Write the symbol for the nonmetal represented in the first word.
Translate its prefix into a number and use that as the subscript.
If there is no prefix, do not use a subscript (representing “1”).
2) Write the symbol for the nonmetal represented by the second
word. Translate its prefix into a number and use that as the
subscript. If the second word begins with “mono-“, do not use
a subscript (representing “1”).
UNIT V - NOMENCLATURE
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Formula  Name
YES
Is the first
symbol “H”?
YES
Is there only a
nonmetal or “CN”
after the “H”??
NO
NO
Is the first symbol
a metal or NH4?
YES
BINARY ACID
1) Use the prefix “hydro-“ on the
first word.
2) Remove the “-ide” prefix from the
name of the anion and replace it
with “-ic”
3) Use “acid” as the second word.
TERNARY ACID
1) Find the name of the anion. If it ends in “-ate”,
replace it with “-ic”. If it ends in “-ite”, replace
it with “-ous”.
2) Use “acid” as the second word.
IONIC COMPOUND
1) Find the name of the cation from the periodic table if it is a metal.
NH4 is ammonium. If the metal is a transition metal, find its positive charge and include that next to the first word as a roman
numeral (excepting silver, aluminum, cadmium, and zinc).
2) If the anion is a nonmetal, find its name on the periodic table, and
change the ending to “-ide”. If the anion is polyatomic, find its
name on the polyatomic ion sheet.
NO
MOLECULAR COMPOUND
1) Find the name of the first nonmetal represented in the formula.
If the subscript is greater than one, give it the appropriate prefix.
2) Find the name of the second nonmetal represented in the
formula. Give it the appropriate prefix, using “mono-“ for one.
UNIT V - NOMENCLATURE
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