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Sources and Uses Planetary gas giants and moons

contain mostly methaneo J upiter, Saturn, Uranus, Neptuneo Titan

Petroleum and fossil fuels

Natural gas

Methanogenic bacteria

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Isomers General Formula: CnH2n+2

Isomerso Molecules having the same formula but different structures

Constitutional Isomerso Isomers varying in the connectivity of their atoms

o E.g. Linea r vs b ranched alkanes

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Systematic Nomenclature IUPAC System

o Makes use of prefixes

Meth- (1)

Eth- (2)

Prop- (3)

But- (4)

Pent- (5)

Hex- (6) Hept- (7)

Oct- (8)

Non- (9)

Dec- (10)

Undec- (11)

Dodec- (12)

Tridec - (13)

Tetradec- (14)

Pentadec- (15) Icos- (20)

Henicos- (21)

Triacon- (30)

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Systematic Nomenclature IUPAC System

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Systematic Nomenclature IUPAC System for branched alkanes

1. Locate the longest continuous chain of carbon atoms. This chaindetermines the parent name.

2. Number the longest chain beginning with the end of the chain nearer thesubstituent

3. Use the numbers obtained from # 2to designate the location of thesubstituent

Substituent name: prefix +-y l

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Systematic Nomenclature IUPAC System for branched alkanes

4. When two or more substituent are present, give each substituent anumber corresponding to its location on the longest chain

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Systematic Nomenclature IUPAC System for branched alkanes

5. When substituent are present on the same carbon, use that numbertwice

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Systematic Nomenclature IUPAC System for branched alkanes

6. When two or more groups of the same substituent are identical, idicatethis by the use of prefixes d i-, tri-, te tra -

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Systematic Nomenclature IUPAC System for branched alkanes

7. When two chains of equal length compete for selection as the parentchain, choose the chain with the greater number of substituent

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Systematic Nomenclature IUPAC System for branched alkanes

8. When branching occurs at an equal distance from either end of thelongest chain, choose the name that gives the lower number at the firstpoint of difference

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Systematic Nomenclature IUPAC System for branched alkyl substituent

o Three-carbon group

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Systematic Nomenclature IUPAC System for branched alkyl substituent

o Four-carbon groups

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Systematic Nomenclature IUPAC System for branched alkyl substituent

o Five-carbon group

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Classification of Carbon

primary

tertiary secondary

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Cycloalkanes Alkanes that form one or more closed-ring structures

Monocyclic alkanes: CnH2n

Bicyclic Compounds

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