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Transcript
Chemistry Unit 6
Chemical Formulas
and
Chemical Compounds
Heart cell rhythm depends on the opening and
closing of a complex series of valves on the cell
membrane, called ion channels. Some valves let
certain ions like potassium (K+) flow out, others
let different ions like sodium (Na+) flow in. There
are also pumps that actively move ions one
direction or another.
Elements combine to form
bonds
Covalent Bonds
-Electrons are shared
-Usually between two nonmetals
Ionic Bonds
-Electrons are transferred
-Usually between a metal
and a non-metal or
polyatomic ions
EXAMPLE: carbon dioxide
EXAMPLE: sodium chloride
Different systems of naming depending on the type of bond…BE CAREFUL!
Ions
• Cation: A positive ion
• Mg2+, NH4+
• Anion: A negative ion
• Cl-, SO42• Ionic Bonding: Force of
attraction between oppositely
charged ions.
Bohr Model of Sodium
+1
How
many many
Now,
What’s
Howhow
many
the
electrons
electrons
does
net
protons
chargedoes
on
does
Na
Na
Na?
Nahave?
have?
have?
Protons: 11 × +1 = 11
Electrons: 10
11 × -1 = -11
-10
+1
0
Na
How
Now
Does
How
many
does
can
Na
valence
Na
satisfy
we satisfy
satisfy
electrons
thethe
the
octet
octet
octet
does
rule?
Na
rule?
rule?
have?
Predicting Ionic Charges
Group 1: Lose 1 electron to form 1+ ions
H+
Li+ Na+
K+
Predicting Ionic Charges
Loses 2 electrons to form
Group 2: 2+ ions
Be2+
Mg2+
Ca2+
Sr2+
Ba2+
Predicting Ionic Charges
B3+
Al3+
Ga3+
Group 13: Loses 3
electrons to form
3+ ions
Predicting Ionic Charges
Neither! Group 14
elements rarely form
ions.
Group 14: Lose 4
electrons or gain
4 electrons?
Bohr Model of Phosphorous
What is the net
charge of P?
-3
Protons: 15 × +1 = 15
Electrons: 18 × -1 = -18
-3
P
How
Now
many
does
valence
P we
satisfy
electrons
octet
does
rule?
P rule?
have?
Does
How
Pcan
satisfy
satisfy
thethe
octet
the
rule?
octet
Predicting Ionic Charges
N3- Nitride
P3- Phosphide
As3- Arsenide
Group 15: Gains 3
electrons to form
3- ions
Predicting Ionic Charges
O2- Oxide
S2- Sulfide
Se2- Selenide
Group 16: Gains 2
electrons to form
2- ions
Predicting Ionic Charges
F1- Fluoride
Br1- Bromide
Cl1-Chloride
I1- Iodide
Group 17: Gains 1
electron to form
1- ions
Predicting Ionic Charges
Group 18: Stable
Noble gases do not
form ions!
Predicting Ionic Charges
Groups 3 - 12: Many transition elements
have more than one possible oxidation state.
Iron (II) = Fe2+
Iron (III) = Fe3+
Predicting Ionic Charges
Groups 3 - 12: Some transition elements
have only one possible oxidation state.
Zinc = Zn2+
Silver = Ag+
Cadmium = Cd2+
Writing Ionic Compound Formulas
Example: Barium nitrate
1. Write the formulas for the cation and anion,
including CHARGES!
2. Check to see if charges are balanced. (If
so, skip to step 5)
3. Balance charges , if necessary, using
subscripts.
A. Cross over the charges by using the
absolute value of each ion’s charge as the
subscript for the other ion.
B. Use parentheses if you need more than one
(
Ba
NO33)2) 2
Ba(NO
of a polyatomic ion.
4. Check the subscripts and divide them by
their largest common factor to give the
smallest possible whole-number ratio.
5. Write the formula without the charges.
2+
Not balanced!
Writing Ionic Compound Formulas
Example: Ammonium sulfate
1. Write the formulas for the cation and anion,
including CHARGES!
2. Check to see if charges are balanced. (If
so, skip to step 5)
3. Balance charges , if necessary, using
+)
2-
( (NH
NH4 4)SO
4 4
2SO
subscripts.
A. Cross over the charges by using the
absolute value of each ion’s charge as the
subscript for the other ion.
B. Use parentheses if you need more than one
of a polyatomic ion.
4. Check the subscripts and divide them by
their largest common factor to give the
smallest possible whole-number ratio.
5. Write the formula without the charges.
2
Not balanced!
Writing Ionic Compound Formulas
Names ending in –ide usually, but
not always, represent an element
1. Write the formulas for the cation and anion,from the periodic table.
including CHARGES!
2. Check to see if charges are balanced. (If
so, skip to step 5)
Example: Iron (III) chloride
3. Balance charges , if necessary, using
subscripts.
A. Cross over the charges by using the
absolute value of each ion’s charge as the
subscript for the other ion.
B. Use parentheses if you need more than one
of a polyatomic ion.
4. Check the subscripts and divide them by
their largest common factor to give the
smallest possible whole-number ratio.
5. Write the formula without the charges.
3+
Fe
Cl
FeCl
-
3
3
Not balanced!
Writing Ionic Compound Formulas
Example: Aluminum sulfide
1. Write the formulas for the cation and anion,
including CHARGES!
2. Check to see if charges are balanced. (If
so, skip to step 5)
3. Balance charges , if necessary, using
subscripts.
A. Cross over the charges by using the
absolute value of each ion’s charge as the
subscript for the other ion.
B. Use parentheses if you need more than one
of a polyatomic ion.
4. Check the subscripts and divide them by
their largest common factor to give the
smallest possible whole-number ratio.
5. Write the formula without the charges.
3+
Al
S
Al S
2-
22 33
Not balanced!
Writing Ionic Compound Formulas
Example: Magnesium carbonate
1. Write the formulas for the cation and anion,
including CHARGES!
2. Check to see if charges are balanced. (If
so, skip to step 5)
5. Write the formula without the charges.
CO33
MgCO
2+
Mg
2-
They are balanced!
Practice Problem
Questions 1-4 refer
to the following
generic chemical
formulas.
Which of the above
represents the chemical
formula when A and B
are combined?
A.AB
B.AB2
C. A2B
D.AB3
E.A2B3
1. A=Be
2. A=ammonium
3. A=Al
4. A=Ca
B=Br
B=O
B=NO3-1
B=O
Naming Ionic Compounds
• 1. Cation first, then anion
• 2. Monatomic cation = name of the
element
• Ca2+ = calcium ion
• 3. Monatomic anion = root + -ide
• Cl- = chloride
• CaCl2 = calcium chloride
4. For polyatomic ions, use the name
of that polyatomic ion.
You Practice!!
Name the following compounds:
•
•
•
•
•
•
•
MgCl2
Ag2O
Ca(OH)2
SrS
KClO3
NH4OH
KClO
•
•
•
•
•
•
•
Magnesium Chloride
Silver Oxide
Calcium Hydroxide
Strontium Sulfide
Potassium Chlorate
Ammonium Hydroxide
Potassium Hypochlorite
Naming Ionic Compounds
(continued)
Metals with multiple oxidation states
- some metal forms more than one cation
- use Roman numeral in name
• PbCl2
• Pb2+ is cation
• PbCl2 = lead (II) chloride
How do we know that lead was +2?
The oxidation
number of lead
is +2.
+2 -2
PbCl
-1
2
What is the charge of chlorine ion?
How many chlorine ions does PbCl2 have?
What’s the total charge of the chlorine ions?
Compounds are neutral, so what must the charge
of lead be in order to balance the -2 charge of
chlorine?
Let’s try Fe2O3
The oxidation
number of iron
is +3.
+6
-6
Fe 2 O3
+3
Iron III Oxide
-2
What is the charge of oxygen ion?
How many oxygen ions does Fe2O3 have?
What’s the total charge of the oxygen ions?
What must the charge of iron be in order to
balance the -6 charge of the oxygens?
You practice!!!
Name the following compounds:
• CuO
• CoF3
• SnI4
• FeSO4
• Sn(SO4)2
Copper II Oxide
Cobalt III Fluoride
Tin IV Iodide
Iron II Sulfate
Tin IV Sulfate
Naming Binary Covalent
Compounds
•
•
•
•
•
Compounds between two nonmetals
- First element in the formula is
named first.
- Second element is named as if it
were an anion.
- Use prefixes
- Only use mono on second element -
1
2
3
4
5
– mono
– di
– tri
– tetra
- penta
6 – hexa
7 – hepta
8 – octa
9 – nona
10 – deca
P2O5 = diphosphorus pentoxide
CO2 = carbon dioxide
CO = carbon monoxide
N2O = dinitrogen monoxide
Pause for a Cause #4
Write the formula of the following compounds
(WRITE WHAT YOU SEE DO NOT CHECK OXIDATION STATE!)
a.Phosphorus Pentachloride
b.Carbon Tetrafluoride
c.Dinitrogen Pentaoxide
d.Tetraphosphorous Decaoxide
e.Carbon Monoxide
f. Carbon Disulfide
Diatomic Elements
H2
N2
O2
F2
Cl2
Br2
I2
These elements exist
in nature as diatomic
molecules.
They are most
commonly joined to
another element and
not found alone in
nature. Why?
Acid Nomenclature
• Acids
• Compounds that form H+ in water.
• Formulas usually begin with ‘H’.
• Examples:
• HCl (aq) – hydrochloric acid
• HNO3 – nitric acid
• H2SO4 – sulfuric acid
Acid Nomenclature
Anion
Ending
Binary 
Acid Name
-ide
hydro-(stem)-ic acid
-ate
(stem)-ic acid
-ite
(stem)-ous acid
Ternary
An easy way to remember which goes with which…
“In the cafeteria, you ATE something ICky”
Acid Nomenclature Flowchart
ACIDS
start with 'H'
2 elements
3 elements
hydro- prefix
-ic ending
no hydro- prefix
-ate ending
becomes
-ic ending
-ite ending
becomes
-ous ending
Acid Nomenclature
• HBr (aq)
• 2 elements, -ide

hydrobromic acid

carbonic acid

sulfurous acid
• H2CO3
• 3 elements, -ate
• H2SO3
• 3 elements, -ite
Acid Nomenclature
• hydrofluoric acid
• 2 elements
 H+ F-
 HF (aq)
• sulfuric acid
• 3 elements, -ic
 H+ SO42-  H2SO4
• nitrous acid
• 3 elements, -ous
 H+ NO2-
 HNO2
Name ‘Em!
• HI (aq)
• HCl
• H2SO3
• HNO3
• HIO4
Write the Formula!
• Hydrobromic acid
• Nitrous acid
• Carbonic acid
• Phosphoric acid
• Hydrotelluric acid
Hydrocarbons - molecules that possess hydrogen and carbon
Alkanes – hydrocarbons with only C-C single bonds.
Example:
Butane CH3CH2CH2CH3 C4H10
CnH2n+2
Alkenes – hydrocarbons with C=C double bonds.
Example:
Butene CH3CH=CHCH3
Alkynes – hydrocarbons with C
Example:
Butyne
CH3C
C4H8
CnH2n
C triple bonds.
CCH3
C4H6
CnH2n-2
Alcohols – R-OH (-OH is hydroxyl group, NOT hydroxide)
Example:
CH3OH Methanol
Basic Naming of Hydrocarbons
Hydrocarbon names are based on: 1) type,
2) # of carbons, 3) side chain type and position
1) name will end in -ane, -ene, or -yne
2) the number of carbons is given by a “prefix”
1 meth- 2 eth- 3 prop- 4 but- 5 pent6 hex- 7 hept- 8 oct- 9 non- 10 decActually, all end in a, but a is dropped when next
to a vowel. E.g. a 6 C alkene is hexene
Q - What names would be given to these:
7C, 9C alkane heptane, nonane
2C, 4C alkyne ethyne, butyne
1C, 3C alkene methene, propene
Mnemonic for First Four Prefixes
First four prefixes
•
•
•
•
MethEthPropBut-
Monkeys
Eat
Peeled
Bananas
Other Prefixes
Decade
?
Decimal
• Pent• Oct-
• Dec-
Decathalon • Hex-, Hept-, Non-
Organic Compounds
Containing Oxygen
• An alcohol is a compound obtained by
substituting a hydroxyl group (-OH) for an
–H atom on a carbon atom of a hydrocarbon
group.
• Some examples are
CH3 OH
CH3 CH2 OH
methanol
ethanol
OH
CH3
CH
propanol
CH3
Practice-Give the name or
formula
a.
b.
c.
d.
Butane
Pentene
Methanol
C2H4
e. C7H15OH
If given the formula……..
• 1st determine if the compound is a
binary (molecular) compound
– If all the elements in the compound are
non-metals or metalloids the compound is a
binary compound.
– Use prefixes to name the compound.
– CHARGES DON’T MATTER, DON’T WRITE
CHARGES!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
– DON’T SWITCH THE PREFIXES!!!!!!!!!!!!!!!!!!!!
If given the formula……..
• If the compound is not a binary
compound, name the compound like an
ionic compound.
– Use roman numerals to depicted the charge
for Pb, Sn, and transition metals (except
Zn, Ag, Cd).
If given the name…..
• 1st check for prefixes.
– If prefixes are present, the compound is
probably a binary compound.
– DON’T WORRY ABOUT CHARGES, DON’T
WRITE CHARGES, JUST WRITE WHAT
YOU SEE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
– ***Remember some polyatomic ions have
prefixes (bicarbonate, dichromate,
dimercury). Write these like ionic
compounds.
If given the name…..
• If the compound is not a binary
compound, use the rules for writing ionic
compounds.
– Make sure to use the correct charges.
– Make sure you don’t change the subscripts
of the polyatomic ions.
– THE ANSWER DOES NOT HAVE ANY
CHARGES!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Rules for oxidation numbers
1. Oxidation number for elements is zero.
N2, O2, Na(s),Co(s), He (g)
2. Oxidation number of monatomic ions
is the same as their charge
Group IA = +1 Al3+, Zn2+, Cd2+, Ag+
Group IIA = +2
3. Oxidation number of oxygen in most compound
is –2. Exceptions: O2- (peroxides)–1
4. Oxidation number of hydrogen is +1 with
Non-metals and -1 with metals.
Rules for Oxidation Numbers
1.
All elements are zero:
Oxidation #
Rules for Oxidation Numbers
1.
All elements are zero:
N2
Oxidation #
Rules for Oxidation Numbers
1.
Oxidation #
All elements are zero:
N2
0
Rules for Oxidation Numbers
1.
Oxidation #
All elements are zero:
N2
Pb
0
Rules for Oxidation Numbers
1.
Oxidation #
All elements are zero:
N2
0
Pb
0
Rules for Oxidation Numbers
1.
Oxidation #
All elements are zero:
N2
0
Pb
0
Na
Rules for Oxidation Numbers
1.
Oxidation #
All elements are zero:
N2
0
Pb
0
Na
0
Rules for Oxidation Numbers
1.
Oxidation #
All elements are zero:
N2
0
Pb
0
Na
0
O2
Rules for Oxidation Numbers
1.
Oxidation #
All elements are zero:
N2
0
Pb
0
Na
0
O2
0
Rules for Oxidation Numbers
2.
Ions are their charge
Na+
Oxidation #
Rules for Oxidation Numbers
2.
Oxidation #
Ions are their charge
Na+
+1
Rules for Oxidation Numbers
2.
Oxidation #
Ions are their charge
Na+
Br-
+1
Rules for Oxidation Numbers
2.
Oxidation #
Ions are their charge
Na+
+1
Br-
-1
Rules for Oxidation Numbers
3.
The oxidation number of O
in a compound is –2.
Na2O
Oxidation #
Rules for Oxidation Numbers
3.
Oxidation #
The oxidation number of O
in a compound is –2.
Na2O
-2
Rules for Oxidation Numbers
3.
Oxidation #
The oxidation number of O
in a compound is –2.
Na2O
CO2
-2
Rules for Oxidation Numbers
3.
Oxidation #
The oxidation number of O
in a compound is –2.
Na2O
-2
CO2
-2
Rules for Oxidation Numbers
3.
Oxidation #
The oxidation number of O
in a compound is –2.
Na2O
-2
CO2
-2
O2
Rules for Oxidation Numbers
3.
Oxidation #
The oxidation number of O
in a compound is –2.
Na2O
-2
CO2
-2
O2
0
Rules for Oxidation Numbers
3.
Oxidation #
The oxidation number of O
in a compound is –2 or in
peroxides -1.
Na2O
-2
CO2
-2
O2
0
HOOH
Rules for Oxidation Numbers
3.
Oxidation #
The oxidation number of O
in a compound is –2 or in
peroxides -1.
Na2O
-2
CO2
-2
O2
0
HOOH
-1
Rules for Oxidation Numbers
4.
The oxidation number for H
in a compound is +1.
Oxidation #
Rules for Oxidation Numbers
4.
The oxidation number for H
in a compound is +1.
H2O
Oxidation #
Rules for Oxidation Numbers
4.
Oxidation #
The oxidation number for H
in a compound is +1.
H2O
+1
Rules for Oxidation Numbers
4.
Oxidation #
The oxidation number for H
in a compound is +1
H2O
C12H24O11
+1
Rules for Oxidation Numbers
4.
Oxidation #
The oxidation number for H
in a compound is +1
H2O
+1
C12H24O11
+1
Rules for Oxidation Numbers
4.
Oxidation #
The oxidation number for H
in a compound is +1
H2O
+1
C12H24O11
+1
H2
Rules for Oxidation Numbers
4.
Oxidation #
The oxidation number for H
in a compound is +1
H2O
+1
C12H22O11
+1
H2
0
Rules for Oxidation Numbers
4.
Oxidation #
The oxidation number for H
in a compound is +1 or in
metal hydrides -1.
H2O
+1
C12H24O11
+1
H2
NaH
0
Rules for Oxidation Numbers
4.
Oxidation #
The oxidation number for H
in a compound is +1 or in
metal hydrides -1.
H2O
+1
C12H24O11
+1
H2
NaH
0
-1
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
2SO4
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
oxidation #s
2SO4
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
oxidation #s
-2
2SO4
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
oxidation #s
-2
2SO4
Total charge
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
oxidation #s
-2
2SO4
Total charge
-8
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
oxidation #s
-2
2SO4
Total charge
-8 = -2
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
oxidation #s
-2
2SO4
Total charge
+6 -8 = -2
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
oxidation #s
+6 -2
2SO4
Total charge
+6 -8 = -2
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
oxidation #s
+6 -2
2SO4
Total charge
+6 -8 = -2
+6
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
3PO4
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
oxidation #s
3PO4
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
oxidation #s
-2
3PO4
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
oxidation #s
-2
3PO4
Total charge
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
oxidation #s
-2
3PO4
Total charge
-8
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
oxidation #s
-2
3PO4
Total charge
-8 = -3
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
oxidation #s
-2
3PO4
Total charge
+5 -8 = -3
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
oxidation #s
+5 -2
3PO4
Total charge
+5 -8 = -3
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
oxidation #s
+5 -2
3PO4
Total charge
+5 -8 = -3
+5
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
2Cr2O7
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
oxidation #s
2Cr2O7
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
oxidation #s
-2
2Cr2O7
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
oxidation #s
-2
2Cr2O7
Total charge
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
oxidation #s
-2
2Cr2O7
Total charge
-14
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
oxidation #s
-2
2Cr2O7
Total charge
-14 = -2
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
oxidation #s
-2
2Cr2O7
Total charge
+12 -14 = -2
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
oxidation #s
-2
Divide by 2
2Cr2O7
Total charge
+12 -14 = -2
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
oxidation #s
+6
-2
2Cr2O7
Total charge
+12 -14 = -2
Rules for Oxidation Numbers
5.
the
the
All other oxidation numbers are assigned so that
sum of all of the oxidation numbers is equal to
charge on the chemical species.
Oxidation #
oxidation #s
+6
-2
2Cr2O7
Total charge
+12 -14 = -2
+6
Oxidation #
Ca(NO3)2
Oxidation #
+2
Ca(NO3)2
Oxidation #
+2
Ca(NO3)2
+2
Oxidation #
Na2C2O4
Oxidation #
+1
-2
Na2C2O4
+2
-8 = 0
Oxidation #
+1
-2
Na2C2O4
+2
+6 -8 = 0
Oxidation #
+1
+3 -2
Na2C2O4
+2
+6 -8 = 0
+3
Oxidation #
CH3COOH
Oxidation #
Rewrite
C2H4O2
Oxidation #
Rewrite
+1 -2
C2H4O2
+4 -4 = 0
0
Oxidation #
Zn(OH)42-
Oxidation #
+2 -2 +1
Zn(OH)42-
+2 -8 +4 = -2
+2
Oxidation #
H2PtCl6
Oxidation #
+1 +4 -1
H2PtCl6
+2 +4 -6 = 0
+4
Oxidation #
Al(NO3)3
Oxidation #
+3 +5 -2
Al(NO3)3
+3 +15 -18 = 0
+5
Oxidation #
H3PO3
Oxidation #
+1 +3 -2
H3PO3
+3 +3 -6 = 0
+3
Oxidation #
Na2O2
Oxidation #
+1 -2
Na2O2
+2 -4 = 0
Exception - does not work, O must be 1
Oxidation #
+1 -1
-1
Na2O2
+2 -2 = 0
Exception - does not work, O must be 1
Oxidation #
CaH2
Oxidation #
+2 +1
CaH2
+2 +2 = 0
Exception - does not work, H must be
-1
Oxidation #
+2 -1
-1
CaH2
+2 -2 = 0
Exception - does not work, H must be
-1
Oxidation #
Fe(H2O)5(OH)2+
Oxidation #
0
-1
Fe(H2O)5(OH)2+
Water has a charge of 0
OH has a charge of -1
Oxidation #
0
-1
Fe(H2O)5(OH)2+
? + 0
-1
= +2
Oxidation #
0
-1
Fe(H2O)5(OH)2+
? + 0
-1
+3
= +2
Assign oxidation numbers to all of the elements:
Li2O
Li = +1
O = -2
PF3
P = +3
F = -1
HNO3 H = +1
MnO4-
N = +5 O = -2
Mn = +7 O = -2
Cr2O72- Cr = +6 O = -2
What is the oxidation state of the highlighted eleme
P2O5 +5
diphosphorous pentoxide
NaH
-1
sodium hydride
SnBr4 +4
tin (IV) bromide
BaO2 -1
barium peroxide