350 likes | 715 Vues
Chapter #20 Carbon and Hydrocarbons NearingZero.net. Chapter 20.1. Carbon is found in nature both as an element and in combined form. 17 th abundant element in the Earth’s crust by mass. Found in all living things, tissue and in the foods we eat.
E N D
Chapter #20 Carbon and Hydrocarbons NearingZero.net
Chapter 20.1 • Carbon is found in nature both as an element and in combined form. • 17th abundant element in the Earth’s crust by mass. • Found in all living things, tissue and in the foods we eat. • Is also found in fuels (coal, petroleum, natural gas, wood.)
Allotropes of carbon • Diamond is a colorless, crystalline, solid form of carbon. • Hardest material known. • Most dense form of carbon. • Extremely high melting point ( 3500*C) • Used industrially for cutting, drilling, and grinding • Graphite is a soft, black, crystalline form of carbon that conducts electricity. • Feels greasy and crumbles easily. • Used in pencil lead • Extremely high melting point (3652*C) • Used in sporting goods and aircraft. • Fullerenes are dark-colored solids made of spherically networked carbon-atom cages.
Fullerenes • Discovered in the mid-1980’s • Are part of soot that forms when carbon-containing materials are burned with limited oxygen • Most stable form is C60 • Because of its structural resemblance to geodesic domes…they names C60 “Buckminsterfullerene” in honor of geodesic dome architect, Buckminster Fuller. • Resembles a soccer ball called “Buckyball”
Chapter 20.2 • Organic compounds are covalently bonded compounds containing carbon, excluding carbonates and oxides. • The diversity of organic compounds results from the uniqueness of carbon’s structure and bonding. • Carbon’s electronic structure allows it to bind to itself and form chains and rings, to bind covalently to other elements, and to bind to itself and other elements in different arrangements.
Catenation the covalent binding of an element to itself to form chains or rings. • Hydrocarbons are the simplest organic compounds, composed of only carbon and hydrogen. • Structural Formula indicates the number and types of atoms present in a molecule and also shows the bonding arrangement of the atoms. CH3-CH2-CH3 Condensed formula
Isomers are compounds that have the molecular formula but different structures. • Structural isomer are isomers in which the atoms are bonded together in different orders 2-methylpropane
Geometric isomers are isomers in which the order of atom bonding is the same but the arrangement of atom in space is different. • Cis groups on the same side • Trans groups are on opposite side (Cl) H Cl Cis Trans
Chapter 20.3 • Saturated hydrocarbons are hydrocarbons in which each carbon atom in the molecule forms four single covalent bonds with other atoms. • Alkanes are hydrocarbons that contain only single bonds. (No Double Bonds). Formula CnH2n+2 For every Carbon 4 hydrogens
Cycloalkanes are alkane in which the carbon atoms are arranged in a ring, or cyclic structure. Formula CnH2(n) C5H2(5) = C5H10 Cyclopentane
Alkyl groups are groups of atoms that are formed when one hydrogen atom is removed from an alkane molecule. • Alkyl groups are named by replacing the suffix –ane of the parent alkane with the suffix -yl
Rules for Alkane Nomenclature • Name the parent hydrocarbon. Find the longest continuous chain of carbons. Add the suffix –ane to the prefix. 7 carbons is the longest chain. So the parent name is heptane
Add the names of the alkyl groups. Add the names in front of the parent name in alpha order. If more than one group has the same name add di-, tri-,tetra…. ethly methylheptane ethyl methyl
Number the carbon atoms in the parent hydrocarbon. IF one or more alkyl groups are present, number the carbon atoms in the continuous chain so that the alkyl groups have the lowest position #’s. If there are 2 equal lowest position numbers with 2 different alkyl groups, give the lowest number to the alpha order.
Insert position numbers. Put the position #’s of each alkyl group in from of the name of that alkyl group. • Punctuate the name. #’s from name hyphen.If there is more than 1 #...put commas in between #’s. 3-ethyl-2-methyl heptane
Examples • Sample problems in text pgs. 639-641 • Them OUT 1. 2.
Rules for Cycloalkane Nomenclature • Name the parent hydrocarbon. Count the # of carbons in the ring. Add the prefix cyclo-. Add the suffix –ane to the prefix. 6 carbons so cyclohexane
Add the names of the alkyl groups. If more than one of the same alkyl group is present use di-, tri-, tetra-… methyl methyl methyl methylcyclohexane Dimethyl
Number the carbon atoms in the parent hydrocarbon. IF one or more alkyl groups are present, number the carbon atoms in the ring so that the alkyl group that comes 1st alphabetically has #1. Then, # in the direction that gives the rest of the alkyl groups the lowest numbers possible. 1 11 2
Insert position numbers. • Punctuate the name. 1,2-dimethylcyclohexane
Natural gas is a fossil fuel composed primarily of alkanes containing one to four carbon atoms. • Petroleum is a complex mixture of different hydrocarbons that varies greatly in composition. Contain from 1 to more than 50 carbon atoms. • Octane rating of a fuel is a measure of its burning efficiency and its antiknock properties.
Chapter 20.4 • Unsaturated hydrocarbons are hydrocarbons in which not all carbon atoms have four single covalent bonds. (Double and triple bonds).
Alkenes are hydrocarbons that contain double covalent bonds.
Rules for Alkene Nomenclature • Name the parent hydrocarbon. Locate the longest continuous chain that contains the double bond(s). If there is only one double bond, add the suffix –ene to the prefix. If there is more than one double bond, modify the suffix to indicate the number of double bonds. 2=adiene, 3=atriene… 4 carbons 1 double bond Butene
Methyl • Add the names of the alkyl groups. • Dimethylbutene Methyl
Number the carbon atoms in the parent hydrocarbon. Number the chain so that the 1st carbon in the double bond has the lowest number. IF numbering from both ends gives equivalent positions for two double bonds, then number from the end nearest the first alkyl group.
Insert position numbers. Place double-bond position numbers immediately before the name of the parent hydrocarbon alkene. • Place alkyl group position numbers immediately before the mane of the corresponding alkyl group. • Punctuate the name.
Alkynes are hydrocarbons with triple covalent bonds. Propyne
Rules for naming Alkynes • Name the parent hydrocarbon. Locate the longest continuous chain that contains the Triple bond(s). If there is only one triple bond, add the suffix –yne to the prefix. If there is more than one triple bond, modify the suffix to indicate the number of double bonds. 2=adiyne, 3=atriyne… • Add the names of the alkyl groups • Number the carbon atoms in the parent hydrocarbon. Number the carbon atoms in the chain so that the 1st carbon atom in the triple bond nearest the end of the chain has the lowest number. If numbering from both ends gives the same positions for two triple bonds, then number from the end nearest the 1st alkyl group. • Insert position numbers. • Punctuate the name.
Aromatic hydrocarbons are hydrocarbons with six-membered carbon rings and delocalized electrons. • Benzene is the primary aromatic hydrocarbon. Benzene
Aromatic Hydrocarbon Nomenclature • Name the parent hydrocarbon. The parent hydrocarbon is the benzene ring. • Add the names of alkyl groups. • Number the carbon atoms in the parent hydrocarbon. If there are 2 or more alkyl groups attached to the benzene ring, number the carbon atoms in the ring. Assign position number one to the alkyl group that comes 1st alpha. Then number in the direction that gives the rest of the alkyl groups the lowest #’s. • Insert position numbers. • Punctuate the name.
Functional Groups • Halogens- end in o- • 1-Chloropentane Cl-C-C-C-C-C • Alcohol end in –nol • Pentanol C-C-C-C-C-OH
Work Cited • Cartoon. Aug. 11, 2006. http://www.nearingzero.net/sbunch5.html • “Buckyball”. May 10, 2007. http://www.ydae.purdue.edu/ANE/images/colorBuckyball.jpg • “Butane”. May 11, 2007. http://www.purchon.com/chemistry/images/butane.gif • “2-methylpropane”. May 11, 2007. http://www.chemistry-help.info/2-methylpropane.gif • “1,2-dichloroethane trans”. May 11, 2007. http://content.answers.com/main/content/wp/en-commons/thumb/5/5d/150px-1,2-dichloroethane.png • “Cyclopentane”. May 11, 2007. http://www.chemvc.com/~tim/cyclopentane.jpg • “Prefix chart”. May 11, 2007. http://www.schoolisland.com/review/reference/chem%20table%20p.gif • “Propane”. May 13, 2007. http://ibchem.com/IB/ibfiles/organic/org_img/propane.gif
“Methane, Ethane, Propane”. May 13, 2007. http://cache.eb.com/eb/image?id=16894 • Cyclohexane”. May 13, 2007. http://www.elmhurst.edu/~chm/vchembook/images/515cyclopentane.GIF • “Ethene, Butene, Propene, Pentene”. May 14, 2007. http://www2.milwaukee.k12.wi.us/madison/dept01/science/kdog/notes/alkenes.gif • “Propyne”. May 14, 2007. http://hyperphysics.phy-astr.gsu.edu/hbase/organic/imgorg/propyne.gif • “Benzene”. May 14, 2007. http://www.amacad.org/images/benzene.gif