Nomenclature - KalkmanChemistry

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Transcript Nomenclature - KalkmanChemistry

Nomenclature
Naming and Formula Writing
Nomenclature

A term that describes the system of principles,
procedures, rules, or terms related to naming.
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We use nomenclature to have a uniform set of
rules for naming and writing formulas for
chemical compounds.
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The IUPAC (International Union of Pure and
Applied Chemistry) establishes these rules.
Review of Key Vocabulary

Ionic Compounds – contain bonds between
metals and nonmetals
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A bond involving a TRANSFER of electrons
A bond between cations and anions
Cation – An atom that has lost one or more
electrons. It has a positive (+) charge.
 Anion – An atom that has gained one or more
electrons. It has a negative (-) charge.
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More Key Vocabulary
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Binary Compound – A substance that has only
2 different elements.
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MgCl2
NaCl
H2O
Ternary Compound – A substance that has 3
or more different elements.
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NaOH
H2SO4
CH3Cl
More Key Vocabulary
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Prefix – A few letters placed at the
beginning of a word to change its
meaning.
Nonmetal
 Carbon dioxide – CO2
 Carbon monoxide – CO
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More Key Vocabulary
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Ending / Suffix – A few letters placed at
the end of a word to change its meaning.
Laughable
 Portable
 Calcium Sulfate – CaSO4
 Calcium Sulfite – CaSO3
 Calcium Sulfide – CaS
 Calcium Oxide - CaO
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Ionic Nomenclature
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Always write the cation and then the
anion.
NaCl – NEVER ClNa
 Sodium Chloride – NEVER Chloride Sodium
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Binary Ionic Nomenclature
(Formula  Name)
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1-State the name of the cation
2-State the name of the anion
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For single elements, drop the ending, substitute the suffix –ide
Cl = Chlorine  Chloride
F = Fluorine  Fluoride
Br = Bromine  Bromide
I = Iodine  Iodide
O = Oxygen  Oxide
S = Sulfur  Sulfide
N = Nitrogen  Nitride
P = Phosphorus  Phosphide
C = Carbon  Carbide
Practice Binary Ionic Naming
CaCl2 – Calcium chloride
 MgO – Magnesium oxide
 AlF3 – Aluminum fluoride
 SrBr2 – Strontium bromide
 Ba3N2 – Barium nitride
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More Key Vocabulary
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Subscript – A number that is written
smaller and to the lower right of an
element or group of elements telling you
how many of that element or group there
are.
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H2O
Mg(ClO3)2
More Key Vocabulary
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Superscript – A number that is written
smaller and to the upper right of an
element or group of elements telling you
the charge of the element or group of
elements.
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H3O+
Ca+2
SO4-2
N+3
Binary Ionic Nomenclature
(Name  Formula)
A little more difficult
 1 - Write the symbol of cation and anion
including charge
 2 - Use subscripts to balance the charge
of the compound
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do not need to write a 1 – it is assumed
 All ionic compounds have a neutral charge

Binary Ionic Nomenclature
(Name  Formula)
Calcium Bromide
 Ca+2
Br
There is a +2 charge and a -1 charge
 An extra -1 charge is needed Ca+2 Br- Br
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+2 -1 -1 = 0
Need 1 calcium and 2 bromine
CaBr2
“Crisscross” Method
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Charge of the cation becomes the subscript for
anion
 Charge of the anion becomes the subscript for
the cation
 Aluminum Sulfide
Check Work
 Al+3 S-2  Al2S3
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Notice the + or – charge is dropped
Simplify to smallest whole numbers
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Mg+2 O-2  Mg2O2  MgO
Practice Binary Ionic Formula Writing
Calcium Sulfide – CaS
 Barium Chloride – BaCl2
 Lithium Fluoride – LiF
 Aluminum Nitride – AlN
 Sodium Phosphide – Na3P
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More Key Vocabulary
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Transition Element – An element in group 3
through 12 on the periodic table.
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Oxidation State – A possible charge for an ion
of a given element.
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Located in top right corner of element square on PT
All “free elements” have oxidation states of ZERO
Many elements only have one oxidation state
Many (BUT NOT ALL) transition elements have
more than one oxidation state
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Can have different charges!
Some, but only a few, other metals have multiple
oxidation states
More Key Vocabulary
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Roman Numerals – A numeral system
established in ancient Rome. The system is
based on certain letters which combine to
signify a number.
1=I
2 = II
3 = III
4 = IV
5=V
6 = VI
7 = VII
Binary Ionic Nomenclature Multiple
Oxidation States (Formula  Name)
Name the Cation
 In Parenthesis, write the oxidation
number of the cation using Roman
Numerals
 Name the Anion
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Examples: Iron (II) oxide, Iron (III) oxide
Determining Oxidation Number
Based on Formula
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We will use the “Multiply Down, Add Across”
Method
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First, rewrite the formula
Second, below each element, write the number of
each element
Third, write any known charges, or write an “x” for
an unknown charge
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We typically know the charges for nonmetals
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Group 15 = -3
Group 16 = -2
Group 17 = -1
Fourth, multiply down, and then create an algebraic
expression so you may add across.
Multiply Down, Add Across
Fe2O3
# of each
element
Known
Charges
Solve
2 3
Charge of the Compound
(Always 0, unless it is an ion)
X -2
2X + -6 = 0
2X = +6
X = +3
FeO
1 1
X -2
X + -2 = 0
X = +2
The oxidation state of Fe is +3
The oxidation state of Fe is +2
Iron (III) oxide
Iron (II) oxide
Practice Binary Ionic Naming Using
Elements w/. Multiple Oxidation States
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MnBr4 – Manganese (IV) bromide
CoCl3 – Cobalt (III) chloride
Cr2O3 – Chromium (III) oxide
Ni3N2 – Nickel (II) nitride
TiS2 – Titanium (IV) Sulfide
Check to make sure the oxidation state you
think is correct is a possible oxidation state
according to your periodic table
Practice Binary Ionic Formula Writing Using
Elements w/. Multiple Oxidation States
Easier than naming
 Use the “crisscross” method
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Remember to reduce subscripts…
Manganese (VII) sulfide – Mn2S7
 Chromium (VI) phosphide – CrP2
 Copper (II) chloride – CuCl2
 Platinum (IV) Oxide – PtO2
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Final Key Vocabulary
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Polyatomic Ion – A particle that contains
more than one atom and has a positive
or negative charge.
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Table E
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First 3 are cations, the rest are all anions
Ternary Ionic Nomenclature
(Formula  Name)
Same Rules
 Write Cation first, then Anion
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Polyatomic Ions have their own endings
NaClO2 = Sodium chlorite
Practice Ternary Ionic Naming
AgNO3 – Silver nitrate
 CaSO4 – Calcium sulfate
 Na2S2O3 – Sodium thiosulfate
 Zn3(PO4)2 – Zinc phosphate
 KMnO4 – Potassium permanganate
 Hg2O – Dimercury (I) oxide
 NH4Cl – Ammonium chloride
 NH4OH – Ammonium hydroxide
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Ternary Ionic Nomenclature
(Name  Formula)
Trickiest of them all…
 1 - Write the symbol of cation and anion
including charge
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2 - Use subscripts to balance the charge of the
compound
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This may mean a whole polyatomic ion
do not need to write a 1 – it is assumed
3 - Any subscripts for a polyatomic ion need to
be written outside parenthesis that surround
the polyatomic ion.
 May still use “crisscross” method
Ternary Ionic Nomenclature
(Name  Formula)
Aluminum Sulfate
 Al+3 SO4-2
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There is a +3 charge and a -2 charge
 We need 2 +3 charges and 3 +2 charges
 Al+3 Al+3 SO4-2 SO4-2 SO4-2
 +3 +3 -2 -2 -2 = 0
 Need 2 aluminums and 3 sulfates
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Al2(SO4)2
“Crisscross” Method w/. Polyatomic Ions
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Charge of the cation becomes the subscript for
anion
 Charge of the anion becomes the subscript for
the cation
 Iron (II) hydroxide
 Fe+2 OH-  Fe(OH)2
Check Work
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YOU NEED PARENTHESIS
There are not 2 H’s, there are 2 OH’s
Simplify to smallest whole numbers
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Ca+2 S2O3-2  Ca2(S2O3)2  CaS2O3
Practice Ternary Ionic Formula Writing
Calcium Sulfite – CaSO3
 Ammonium sulfide – (NH4)2S
 Cobalt (III) phosphate – CoPO4
 Copper (II) nitrate – Cu(NO3)2
 Ammonium dichromate – (NH4)2Cr2O7
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Ionic Nomenclature Mega Practice
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Ca3(PO4)2
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Potassium bromide
Mn2O7
Strontium perchlorate
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CuO2
Manganese (VII) oxide
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Ba3N2
Copper (II) peroxide
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Potassium cyanide
KBr
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Na2S
Barium nitride
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Copper (II) sulfite
KCN
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Iron (III) chloride
CuSO3
Sodium sulfide
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Sodium hydroxide
FeCl3
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Calcium phosphate
NaOH
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Sr(ClO4)2
Chromium (III) nitrite
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Cr(NO2)3
More Key Vocabulary
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Covalent Compounds – contain bonds
between one or two nonmetallic
elements
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Remember when Ionic Bonding was so
short and easy, and Covalent Bonding
was so long and tough?
OPPOSITE HERE
 Naming Covalent Compounds is EASY
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Covalent Prefixes
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Only hard part:
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You need to MEMORIZE these prefixes
# atoms
1
2
3
4
5
Prefix
-mono
-di
-tri
-tetra
-penta
# atoms
6
7
8
9
10
Prefix
-hexa
-hepta
-octa
-nona
-deca
Covalent Nomenclature
(Formula  Name)
Name the elements in the order they are
listed
 Use the prefixes to show how many of
each element
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DON’T use “mono” for the first element
 Avoid difficulty saying words by eliminating
“ao” or “oo” by just using “o”
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Hexaoxide is too difficult to say, just write Hexoxide
Change the ending of the second element
to -ide
Covalent Nomenclature Practice
(Formula  Name)
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N2O – Dinitrogen monoxide
NO2 – Nitrogen dioxide
CO – Carbon monoxide
CO2 – Carbon dioxide
CCl4 – Carbon tetrachloride
NI3 – Nitrogen triiodide
***NH3 – Ammonia
***H2O – Water
CS2 – Carbon disulfide
N2O5 – Dinitrogen pentoxide
*** There are
common names for
these we use instead,
H2O you should know,
NH3 is in your
reference table…
Covalent Nomenclature
(Name  Formula)
Even Easier!
 Use the prefixes to guide you for what
the subscripts need to be
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Dihydrogen monosulfide
Di = 2  H2
 Mono = 1  S
 H2S
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Covalent Nomenclature Practice
(Name  Formula)
Carbon tetrabromide – CBr4
 Iodine dioxide – IO2
 Phosphorus pentachloride – PCl5
 Dichlorine heptoxide – Cl2O7
 Diphosphorus trioxide – P2O3
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Ionic + Covalent Nomenclature
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The trick to naming and formula writing is
determine first if the example is an ionic or
covalent compound.
P4O10
Tetraphosphorus decoxide
Dinitrogen monoxide
N2O
TiCl3
Titanium (III) chloride
Ammonium thiosulfate
(NH4)2S2O3
Calcium Phosphate
Ca3(PO4)2
Ammonia
NH3