1 / 92

Topics 10 and 20 Text CH 25 Oxford p. 61-74

Topics 10 and 20 Text CH 25 Oxford p. 61-74. Organic Review # 1. Organic Chemistry. Chemistry of Carbon compounds More than 90 % of all compounds are carbon compounds Energy sources Petroleum, Coal, Natural Gas Food Proteins, Fats, Carbohydrates, Vitamins, Enzymes, Hormones, Steroids

marlow
Download Presentation

Topics 10 and 20 Text CH 25 Oxford p. 61-74

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Topics 10 and 20 Text CH 25 Oxford p. 61-74

  2. Organic Review # 1

  3. Organic Chemistry • Chemistry of Carbon compounds • More than 90 % of all compounds are carbon compounds • Energy sources • Petroleum, Coal, Natural Gas • Food • Proteins, Fats, Carbohydrates, Vitamins, Enzymes, Hormones, Steroids • Drugs • Anesthetics, Antiseptics, Antibiotics • Materials • Fibers, Fabrics, Plastics, Paints, Dyes, Soaps, Detergents, Explosives

  4. Inorganic Compounds • Compounds that do not contain carbon • Metal carbonates • Carbon monoxide, carbon dioxide

  5. Carbon • Column 14 • Always forms covalent bonds • 1s22s22p2 • 4 valence electrons • Bonds • Four • Tetrahedral arrangement • sp3 hybridized • Three • Trigonal planar arrangement • sp2 hybridized • Two • Linear arrangement • sphybridized

  6. Carbon • Combines with itself and other atoms to form millions of compounds (especially H and O) • Basis of life • C-C bonds and C-H bonds are exceptionally stable • Carbon can form long chains with itself • Carbon can single, double, and triple bond with itself • Carbon can bond into ring structures • Functional groups attach to hydrocarbon chains resulting in greater reactivity

  7. 10.1.11 • Functional Group Flash Cards • Functional groups Worksheet

  8. 10.1.1 Homologous Series • Series of organic compounds that have the same functional groups and differ only by the presence of an extra carbon atom and its associated hydrogens. • Similar chemical properties due to similar functional groups • Represented by the general formula CnH2n+2 • Successive compounds have physical properties that differ in a regular manner as number of C’s and H’s increases.

  9. 10.1.2Changes in Physical Properties • Result of changes that occur in the strength of van der Waal’s forces. • van der Waal’s increase with increasing molar mass • Boiling point • Density • Viscosity

  10. Factors Affecting Physical PropertiesHydrogen Bonds>Diopole-Dipole>van der Waal’s • Van der Waal’s Forces • The greater the molar mass the greater the force which increases boiling point • Dipole-Dipole Forces • The presence of aldehydes, ketones, and halogen functional groups give rise to polarity which increases boiling point. • Hydrogen Bonds • The presence of alcohol, carboxylic acid, amine, amide functional groups give rise to hydrogen bonding

  11. 10.1.13 Solubility • Most organic compounds are non-polar and insoluble in water • Organic compounds with short carbon chains and polar functional groups are soluble in water. The longer the chain, the less soluble the compound. • Carbon chains with carboxylic acids reduce the pH of water when dissolved. • Carbon chains with amines reduce the pH of water when dissolved.

  12. 10.1.3 Empirical, Molecular, Structural Formulas • Full Structural Formula for Butanoic Acid • Condensed Structural Formula for Butanoic Acid CH3CH2CH2COOH • Molecular Formula for Butanoic Acid C4H8O2 Empirical Formula for Butanoic Acid C2H4O

  13. 10.1.6/10.1.10 IUPAC Naming Rules • Step 1—Identify the longest carbon chain. This will determine the prefix of the name • Meth 1 carbon • Eth 2 carbons • Prop 3 carbons • But 4 carbons • Pent 5 carbons • Hex 6 carbons • Hept 7 carbons • Oct 8 carbons • Non 9 carbons • Dec 10 carbons

  14. Step 2 Numbers are assigned to the carbons in the longest chain. Begin numbering at the “busiest” end of the chain.

  15. Step 3--Identify the type of bonding in the chain or ring. This will determine the body of the name • All single bonds/alkane/“an” • One double bond/alkene/”en” • One triple bone/alkyne/”yn” 1-pentyne 2-pentene pentane

  16. Step 4 Identify the functional group joined to the chain or ring. This may be added to the beginning or the end of the name. • Alcohol / OH / ”ol” • Amine / NH2 / ”amino” • Halogen / Cl, Br, I / ”chloro, bromo, iodo”

  17. http://www.chem.ucalgary.ca/courses/351/orgnom/main/basics.htmlhttp://www.chem.ucalgary.ca/courses/351/orgnom/main/basics.html • http://butane.chem.uiuc.edu/cyerkes/Chem104A_BFA05/Genchemref/nomenclature_rules.html

  18. Naming Practice • Covers 10.1.7, 10.1.8, 10.1.9,10.1.10

  19. 10.1.4 Isomers • Different compounds that have the same molecular formula • Alkanes: Butane Pentane • Alkenes b.p. 36.3 b.p. 27.9 b.p. 9.5 But-1-ene 2-methylpropene But-2-ene

  20. 10.1.5 Deduce structural formulas for the isomers of non-cyclic alkanes up to C6 • CH4 • C2H6 • C3H6 • C4H10 • C5H12 • C6H14

  21. 10.1.12 Classification of Alcohols and Haloalkanes

  22. Organic Review # 2

  23. Higher Level Naming Rules • Alcohol -ol9 c,i,l 10 a,e,f 11e 13c • Ketones -one 9e 10 b 13b • Aldehydes -al 9k, 10 d 13a, • Carboxylic acid -oic acid 9d,m,p 13d,n • Amines amino- 11g, 13e,j • Amides -amide 11h • Esters -oate • Nitriles -nitrile 13m

  24. 20.1 Naming Primary Amines (R-NH2) • Naming Amines (R-NH2) • Several different ways accepted • Prefix the longest chain alkane with the word amino • 2-aminopentane • 1-aminohexane • Call them by the longest alkane with the suffix amine • Pentan-2-amine • Propan-1-amine • For small carbon chains, old names are acceptable • Methylamine • Ethylamine

  25. 20.1 Naming Secondary Amines (R-NH-R) • Main name of the amine is taken from from the longest carbon chain attached to the N. The other chain is prefixed as an alkyl group with the location prefixed as N (italicized) N,N-dimethylethanamine Draw this one… N-propylhexanamine

  26. 20.1 Naming Amides (R-CO-NH2) • Amides are named after the longest carbon chain which includes the C from the amide…followed by amide 2-methylpropanamide N-methylethanamide Draw this one… N-ethylpentanamide

  27. 20.1 Naming Esters (R-COO-R’) • Esters take their name from the acid and alcohol from which they are derived. • The first part of the ester is named from the R group of the alcohol • The second part of the name comes of the carboxylic acid anion Note the space between the two words propyl methanoate Methyl ethanoate Draw this one…butyl hexanoate

  28. 20.1 Naming Nitriles (R-CN) • Nitriles used to be called cyanides • Call them by the longest alkane with the suffix nitrile pentanenitrile propanenitrile Draw this one…decanenitrile

  29. 10.2.1 Alkanes • General Formula CnH2n+2 • Low Reactivity • Saturated hydrocarbons • Strong C-C and C-H bonds • Relatively high bond enthalpies • Low polarity • Combustion reactions with oxygen • Substitution reactions with halogens

  30. 10.2.2 Combustion Reactions • Alkanes are flammable • Highly exothermic • One of the most common energy sources • CnH2n+2 + O2 CO2 + H2O • Balancing not difficult if you use the “shortcut”

  31. 10.2.2 Incomplete Combustion • If there is not enough oxygen available, incomplete combustion occurs and CO and C are also produced as products • CO—colorless, odorless, toxic gas • C—black smoke • These products along with lead additives in gasoline are a major source of pollution

  32. 10.3.3 Substitution Reactions • Alkane + Halogen  HCl + substituted alkane • Occur with exposure to sunlight or UV light or very high temperatures • + Cl-Cl  H-Cl + • + Br-Br  H-Br +

  33. Further Substitution • More than one H can be replaced

  34. 10.2.4 Mechanism of a Substitution Reaction • AKA Free Radical Chain Reaction • Three steps • Initiation • Propagation • Termination • Breaking of bonds • Heterolytic • Homolytic

  35. Heterolytic vs. Homolytic fission • Heterolytic Fission • Both of the shared electrons go to one of the bonded atoms • Results in + and – ions. • Homolytic Fission • Each of the two bonded atoms receives one of the electrons • Results in the formation of two free radicals

  36. Mechanism of the Chlorination of Methane

  37. Step 1-- Initiation • Homolytic Fission of halogen molecule occurs forming two free radicals • Each radical is highly reactive

  38. Step 2-- Propagation • When a chlorine free radical comes into contact with methane molecule, it will combine with one of the hydrogens from the methane to produce HCl. The methane is now a methyl free radical. • The methyl free radical is extremely reactive and can come into contact with another chlorine molecule to form chloromethane and another chlorine free radical • Chain reaction! A single chlorine radical can cause up to 10,000 molecules of chloromethane to be formed.

  39. Step 3 –Termination • Occurs when two radicals react together.

  40. Further Substitution • Occurs when chlorine radicals react with substituted products. • Can result in the production of di-, tri-, and tetra-chloromethane.

  41. 10.3 Alkenes • Unsaturated hydrocarbons • Contain at least on C=C • General formula CnH2n

  42. Bond Strength • The C=C double bond ( 612 kJmol-1 ) is stronger than the C-C single bond ( 348 kJmol-1 ) • It is energetically favorable for a double bond to be converted to two single bonds. • Alkenes are more reactive than alkanes and are an important starting point in the synthesis of other organic compounds. • Most important reactions of alkenes are addition reactions.

  43. 10.3.1 Alkenes and Addition Reactions • General Reaction • Pass out Addition Reaction Diagram( Ox p. 65) unsaturated saturated

  44. 10.3.2 Uses of Addition Reactions • Bromination • Pure bromine=red liquid • Bromine Water = yellow orange liquid • Bromine water + Alkene = colorless • Usuful test to indicate the presence of an alkene

  45. 10.3.2 Uses of Addition Reactions • Hydration—formation of ethanol • Ethene is an important product formed in the cracking of oil • Industrial ethanol is formed from adding steam to ethene H2SO4 , H3PO4 , or Al2O3 needed as a catalyst 300 C and 7 atm

  46. 10.3.2 Uses of Addition Reactions • Hydrogenation • Addition of hydrogen to unsaturated vegetable oils • Used to make margarine • Reduced the number of C=C in polyunsaturated fatty acids of vegetable oils, causing the oil to become a solid at room temperature.

More Related