Nomenclature Notes

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AP Chemistry: Chapter 1-2 Notes Outline
September 10 -TEST
By the end of this unit you should be able to:
write key ions and their charges
name and write formulas for ionic compounds
name and write formulas for hydrates
name and write formulas for acids
name and write formulas for molecular compounds
name and write formulas for coordination compounds
name and write formulas for organic compounds
and identify key functional groups
balance chemical equations
count and use significant figures in calculations
convert measurements using dimensional analysis
analyze mass spec data
calculate standard deviation and percent error
Essential Question: How do you use chemical nomenclature rules (IUPAC) to name and write formulas
for inorganic compounds?
Questions to Ponder:
1. Why do ions form?
2. When are roman numerals used in a chemical name?
3. What information is conveyed in the endings –ide, -ite, -ate, in an anion?
Naming Ionic Compounds (metal and nonmetal compounds)
Rules
1. Name the cation:
2. Use Roman Numerals if the metal is a transition metal (Exceptions: Zn, Ag) or Pb and Sn
3. Name the Anion ending in ide unless it is a polyatomic ion
Examples: From Formula to Name
1. AlCl3
4. CoI2
2. LiH
5. Na2SO4
3. Fe2O3
Examples: From Name to Formula (you must know the charges on the ions!)
1. Vanadium (V) fluoride
4. Thallium (III) perchlorate
2. Gallium oxide
5. Barium hydrogen carbonate
3. Titanium (IV) nitrate
6. Rubidium sulfide
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Naming Hydrates – a compound that contains water molecules weakly bound in its crystal
Rules:
1. Name the anhydrous compound (like above)
2. Then a prefix for the number of water molecules followed by the word hydrate.
Examples
1. CuSO4•5H2O
3. Sodium carbonate decahydrate
2. MgSO4•7H2O
4. Sodium thiosulfate pentahydrate
Naming Acids
Rules: Always check the anion of the acid
1. If the anion ends in ide change to hydo________ic acid
2. If the anion ends in ate change to ________ic acid
3. If the anion ends in ite change to ________ous acid
4. If the anion is per____ate change to per_____ic acid
Examples
1. H2S(aq)
5. sulfurous acid
2. H3PO4(aq)
6. hydrobromic acid
3. HNO2(aq)
7. perbromic acid
4. HClO4(aq)
8. carbonic acid
Naming Molecular Compounds (two nonmetals)
Rules: Use prefixes for these compounds
1. Prefix of the first element (mono is optional)
2. Name the first element
3. Prefix of the second element
4. Name of the last element ending in ide
Examples: From Formula to Name
1. PCl5
2. SF6
3. SO3
Examples: From Name to Formula
1. Dinitrogen monoxide
2. Sulfur dioxide
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3. Carbon tetrachloride
K4[Fe(CN)6]
Naming Coordination Compounds
Rules:
1. The name of the cation precedes the name of the anion. (two words)
[Co(NH3)6]Cl3
2. The name of the complex consists of two parts written together as one word. Ligands are
named first, and then the metal atom is named second.
[Ru(NH3)5Cl]Cl2
3. Naming the ligands. Ligand – a molecule or anion bond to a metal through coordination of
its lone pairs.
a. Neutral ligands are given the name of the molecule.
There are several exceptions, which are given in the table.
b. Anionic ligands end in o.
c. The prefixes used to denote the number of ligands is the
same as the prefixes used in molecular compounds. (see
chart above).
4. The complete metal name consists of the name of the metal,
followed by –ate if the complex is an anion, followed by the
oxidation number of the metal (roman numeral).
5. Examples:
a. Na[AgCl2]
b. Pt(NH3)2Cl2
c. CrF63d. Ag(CN)2e. [Cr(H2O)4Cl2]+
f. Hexaamminenickel (II) bromide
g. Sodium tetrachlorooxomolybdate (IV)
h. Tetraamminecarbonatocobalt (III) sulfate
i. Potassium diaquatetrabromovanadate (III)
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Naming Organic Compounds
Alkanes Rules:
1. Add the suffix –ane to the Greek root for the number of carbon atoms in the compound.
General Formula:
Greek roots
# of C
meth-
1
eth-
2
prop-
3
but-
4
pent-
5
hex-
6
hept-
7
Adding an akyl group: When alkane groups appear as a
branch on the normal alkane.
oct-
8
non-
9
When naming the compound with a branch, the longest
chain of carbon atoms are counted starting at the end
closest to the branch.
CH3
|
Example:
CH3-CH2-CH-CH2-CH2-CH3
dec-
10
Examples:
1. CH4
5. butane
2. C2H6
6. octane
3. C7H16
7. propane
4. C10H22
8. pentane
Try these:
1.
3.
CH3CHCH2CH2CH3
|
CH3
CH3
│
CH3─C─CH2─CH3
│
CH3
5. 4-ethyl-3,5-dimethyl nonane
6. 3,3-dimethyloctane
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2. CH3─CH─CH─CH3
│
│
CH3 CH3
CH2─CH3
│
4. CH3─CH2─CH─CH2─CH2─CH3
7. 4-ethyl-3-methylheptane
AlkenesGeneral Formula:
Rules: 1. Find the longest chain containing the double bond. Use the prefixes + the suffix ene.
2. The carbon atoms are numbered from the end nearest the double bond.
3. The position of the double bond must be given as a number written in front of the stem name.
Examples:
1. CH3CH═CHCHCH2CH3
2. CH3CH2CH2CH2CHCH═CHCH3
│
CH2CH2CH2CH2CH3
4. CH3C═CHCHCH3
│
│
CH3 CH2CH3
5. CH3CH2CH2CHCH2CH2CH3
│
CH
║
CH2
3. 2,5-dimethyl-2-heptene
6. CH2═CHCHCH2CH3
│
CH3
AlkynesGeneral Formula:
Rules: : 1. Find the longest chain containing the triple bond. Use the prefixes + the suffix yne.
2. The carbon atoms are numbered from the end nearest the triple bond.
3. The position of the triple bond must be given as a number written in front of the stem name.
Examples:
1. CH3C≡CH
2. CH≡CCHCH3
│
CH2CH3
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3. CH3CHC≡CH
│
CH3
Balance chemical equations
Balance the following:
__O2 
__C6H12O6
+
__CO2
+
__H2
+
__O2 
__H2O
__H2
+
__N2 
__NH3
__NO +
__O2 
__NO2
__NH3 +
__O2  __NO + __H2O
__H2O
Significant Figures:
Why significant figures?
Rules for counting significant figures
1. All nonzero numbers count
2. Captive zeros count
3. Leading zeros don’t count
4. Trailing zeros count if there is a decimal
5. Trailing zeros don’t count if there is no decimal
Examples of counting significant figures:
1. 0.00105 g
2. 0.050080 g
3. 8.050 x 10-3 s
4. 1.008
EXACT NUMBERS: exact numbers have infinite significant figures, and therefore, are not counted
when doing calculations.
Examples:
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Rules for calculating with significant figures:
1. Addition and Subtraction: You are only as good as your least accurate place value
2. Multiplication and Division: You are only as good as your least accurate number of significant
figures
Examples of calculations involving significant figures
1. 12.11 + 18.0 + 1.013 =
3. 1.05 x 10-3  6.135 =
2. 4.56 x 1.4 =
4. 21-13.8 =
Accuracy and Precision
Accuracy-
Precision-
Solving for standard deviation:
1. Make a list of your data by pressing STAT then EDIT and enter the data into L1 (list 1)
2. Calculate the statistics
a. STAT CALC
b. 1 – Var Stats (1) and ENTER
c. ENTER again. Sx is the standard deviation.
Example: Commercial Tylenol contains approximately 500 mg of acetaminophen. A batch of tablets
must contain between 450 – 550 mg of acetaminophen per tablet. Suppose a chemical analysis gave the
following results for a batch of tablets: 428 mg, 479 mg, 442 mg, and 435 mg. Calculate the standard
deviation.
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Convert with Dimensional Analysis
The principle is that you are multiplying several fractions tog tether, but each is the same measurement
so that you are essentially multiplying by 1.
Dimensional Analysis Rules:
1. All numbers must be written as fractions—this includes numbers that are given—so 6.7 grams is
6.7 g
1
2. All subsequent multipliers are written such that the units must cancel: For example:
6.7 g
1lb
x
 0.015lbs . Notice how the grams cancel
1
454 g
3. All numbers on the top of a series of fractions are multiplied and all numbers on the bottom of a
series of fractions are divided. For example:
143.55mL
1L
0.2642gal 4qt 2 pt
x
x
x
x
 0.30341pt . In your calculator you would:
1
1000mL
1L
1gal 1qt
143.55*0.264*4*2/1000=.
Example 1:
One Dimensional Problems – a pencil is 7.00 inches long. What is the length in cm?
Example 2 : Working with multiple dimensions—Convert 55 miles per hour into meters per second.
Example 3: Complex Problems
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