12 Weeks to TAKS Week 11

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12 Weeks to TAKSWeek 11

• Part II

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12 Weeks to TAKS Week 10Objective 4 IPC 7D
The student is expected to relate the chemical
behavior of an element including bonding, to its
placement on the periodic table.
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Ions

• Cation A positive ion
• Mg2, NH4
• Anion A negative ion
• Cl-, SO42-
• Ionic Bonding Force of attraction between
  oppositely charged ions.

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Predicting Ionic Charges
Group (IA) 1
Lose 1 electron to form 1 ions
H
Li
Na
K
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Predicting Ionic Charges
Group (IIA) 2
Loses 2 electrons to form 2 ions
Be2
Mg2
Ca2
Sr2
Ba2
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Predicting Ionic Charges
Group (IIIA) 13
B3
Al3
Ga3
Loses 3 electrons to form 3 ions
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Predicting Ionic Charges
Group (IVA) 14
Many Group IVA (14) elements rarely form ions.
Lose 4 electrons or gain 4 electrons?
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Predicting Ionic Charges
Nitride
N3-
Group (VA) 15
Gains 3 electrons to form 3- ions
Phosphide
P3-
Arsenide
As3-
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Predicting Ionic Charges
Oxide
O2-
Group (VIA) 16
Sulfide
S2-
Gains 2 electrons to form 2- ions
Selenide
Se2-
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Predicting Ionic Charges
Fluoride
Bromide
F1-
Br1-
Group (VIIA) 17
Gains 1 electron to form 1- ions
Chloride
Iodide
Cl1-
I1-
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Predicting Ionic Charges
Group (VIIIA) 18
Stable Noble gases do not form ions!
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Predicting Ionic Charges
Groups 3 - 12
Many transition elements
have more than one possible oxidation state.
Roman numerals are used to indicate the oxidation
state
Iron(II) Fe2
Iron(III) Fe3
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Predicting Ionic Charges
Groups 3 - 12
Some transition elements
have only one possible oxidation state.
Zinc Zn2
Silver Ag
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Writing Ionic Compound Formulas
Example Iron(III) with chloride
1. Write the formulas for the cation and anion,
including CHARGES!
2. Check to see if charges are balanced.
Fe3
Cl-
3. Balance charges , if necessary, using
subscripts. Use parentheses if you need more than
one of a polyatomic ion.
Not balanced!
Fe3
Cl-
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4. Name the ions
Balanced!
Iron(III) chloride
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Example Barium with nitrate
1. Write the formulas for the cation and anion,
including CHARGES!
Ba2
NO3-
2. Check to see if charges are balanced.
3. Balance charges , if necessary, using
subscripts. Use parentheses if you need more than
one of a polyatomic ion.
Not balanced!
( )
Ba2
NO3-
4. Name the ions
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Barium nitrate
Balanced!
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Your Turn!
Example Ammonium with sulfate
1. Write the formulas for the cation and anion,
including CHARGES!
NH4
SO42-
2. Check to see if charges are balanced.
3. Balance charges , if necessary, using
subscripts. Use parentheses if you need more than
one of a polyatomic ion.
Not balanced!
( )
NH4
SO42-
4. Name the ions
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Ammonium sulfate
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Example Aluminum with sulfide
1. Write the formulas for the cation and anion,
including CHARGES!
2. Check to see if charges are balanced.
S2-
Al3
3. Balance charges , if necessary, using
subscripts. Use parentheses if you need more than
one of a polyatomic ion.
Not balanced!
4. Name the ions
S2-
Al3
3
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Aluminum sulfide
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Example Magnesium with carbonate
1. Write the formulas for the cation and anion,
including CHARGES!
Mg2
CO32-
2. Check to see if charges are balanced.
4. Name the ions
They are balanced!
Magnesium carbonate
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Example Zinc with hydroxide
1. Write the formulas for the cation and anion,
including CHARGES!
2. Check to see if charges are balanced.
Zn2
OH-
3. Balance charges , if necessary, using
subscripts. Use parentheses if you need more than
one of a polyatomic ion.
Not balanced!
( )
Zn2
OH-
4. Name the ions
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Zinc hydroxide
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Example Calcium with phosphate
1. Write the formulas for the cation and anion,
including CHARGES!
2. Check to see if charges are balanced.
Ca2
PO43-
3. Balance charges , if necessary, using
subscripts. Use parentheses if you need more than
one of a polyatomic ion.
Not balanced!
4. Name the ions
( )
Ca2
PO43-
Calcium phosphate
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