Transcript Ionic Formulas and Nomenclature

Ionic Formulas and
Nomenclature
Formulas
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What types of elements are found in ionic
compounds?
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What holds the elements together?
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Even though there are ions in ionic
compounds, the overall compound must
be neutral.
Electrolytes
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What type of compounds are electrolytes?
Why are ionic compounds electrolytes?
Consider sodium chloride:
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Consider sucrose (sugar, C12H22O11):
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Is this an electrolyte?
Why?
Is this an electrolyte?
Why?
Consider ammonium chloride (NH4Cl):
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Is this an electrolyte?
Why?
Conductivity of Ammonium
Chloride
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Why does it light up?
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What type of bonding actually occurs in
ammonium chloride?
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Where are the ions in NH4Cl?
Two Types of Ions
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Monatomic ions – ions made of a single
atom.
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Polyatomic ions – ions made of many
atoms
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Polyatomic ions can be found on your
reference table.
Ionic Formulas Activity
Writing Ionic Formulas
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A compound made from barium and phosphate
ions.
Figure out the charges on the ions involved.
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Find the lowest common multiple of the charges:
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LCM of 2 and 3 is 6
When you have 6 total positive charges and 6 total
negative charges the compound will be neutral.
Determine the individual number of ions
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Ba2+
PO43-
To get 6 total positives you need 3 barium ions
To get 6 total negatives you need 2 phosphate ions
Write the formula with those numbers
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Ba3(PO4)2
Writing Ionic Formulas
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Write the formula of the following
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A compound made from aluminum and
hydroxide ions.
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A compound made from magnesium and
sulfur.
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A compound made from strontium and nitrite
ions.
Naming Ionic Compounds
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Based on you already knowing the
charges of the ions involved.
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Does not tell you how many of each ion
there are.
The Rules
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Name the positive ion first
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Na+ = sodium ion
(Leave a couple lines of blank space here)
Name the negative ion last
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Change the name of a monatomic anion to
have an –ide ending.
Polyatomic ions names are not changed
Practice Problems
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Name the following:
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BaCl2
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MgO
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Na3P
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Al2(SO4)3
Those Stupid d-Orbitals
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Consider the following copper oxides:
CuO
Cu2O
Determine the charge on the copper ions in both
compounds.
Multi-valent metals
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Most metal ions can have multiple stable
charges because of the d-orbitals.
The ones that can’t are:
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Group 1
Group 2
Silver (+1)
Zinc (+2)
Aluminum(+3)
For everything that can have a multiple charge
you must specify the charge in the name.
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Use Roman numerals to tell the charge.
The Rules
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Name the positive ion first
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Na+ = sodium ion
Specify the charge of all metal ions with a
Roman numeral
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Except Group 1, Group 2, Ag, Zn, Al
Name the negative ion last
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Change the name of a monatomic anion to
have an –ide ending.
Polyatomic ions names are not changed
Those Stupid d-Orbitals
CuO
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Cu2O
Name the compounds above:
Black = copper(II) oxide
Red = copper(I) oxide
Remember the Roman numeral is the charge
not the number of atoms.
Practice Problems
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Name the following compounds
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Fe2O3
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Co(NO3)2
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CaCO3
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NH4C2H3O2
Practice Problems
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Name the following compounds
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MnO2
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AgCl
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CrN2
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W2O5
Practice Problems
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Write the formulas for the following
compounds:
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Tin(IV) oxide
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Aluminum chloride
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Ammonium sulfide
Practice Problems
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Write the formulas for the following
compounds:
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Potassium dichromate
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Chromium(II) nitrate
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Technetium(VII) oxide