1 / 65

Organic Chemistry

Organic Chemistry. Topic 11. What is Organic Chemistry?. The study of carbon and most carbon compounds “The chemistry of life” … but includes far more compounds than those made by living things. Bonding of Carbon Atoms.

bastien
Download Presentation

Organic Chemistry

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. Organic Chemistry Topic 11

  2. What is Organic Chemistry? • The study of carbon and most carbon compounds • “The chemistry of life” • … but includes far more compounds than those made by living things.

  3. Bonding of Carbon Atoms • Carbon can form so many compounds because carbon atoms easily form covalent bonds with other carbon atoms • Can be single, double, or triple covalent bonds

  4. Bonding of Carbon Atoms • Lewis Dot Diagram of Carbon in ground state • Lewis dot diagram of bonded carbon atom • Enables four covalent bonds • Tetrahedral shape • Angles are actually 109.50

  5. Some Terminology • Organic compounds containing only single bonds are said to be saturated. • Organic compounds containing one or more double or triple bonds are called unsaturated compounds.

  6. More Terminology • Hydrocarbons - organic compounds that contain only hydrogen and carbon atoms • Homologous series - group of related compounds in which each member differs from the one before by one additional unit. • Alkanes • Alkenes • Alkynes

  7. Chemistry Humor • According to a chemist, why is the world so diverse? • Because it's made up of alkynes of people.

  8. Alkanes • All single bonds between carbon atoms • Therefore, all saturated. • As the number of carbon atoms in this homologous series increases, so does the boiling point • Names end with “-ane”

  9. Alkanes • Methane - Natural gas • Ethane - Also natural gas • Propane - outdoor grills/home heating • Butane - lighters • Pentane, Hexane, Heptane, Octane, Nonane, Decane - all found in gasoline • Candle wax - 20 or more carbon atoms • Road Tar - 40 or more carbon atoms

  10. General Formula For Alkanes • Each successive carbon adds two more hydrogen atoms • Let’s develop a general formula for alkanes… • CnH2n+2

  11. Alkenes • Each member of alkene series contains one double covalent bond • Names are same as for alkanes, except change ending to “-ene”. • Ethene - (common name “ethylene”) • Unsaturated

  12. Alkenes • Let’s develop a general formula for “alkenes”…. • CnH2n

  13. Alkynes • Contain one triple bond between carbon atoms • Names are same as for alkanes, except change ending to “-yne”. • Ethyne (common name “acetylene” - used in welding torches)

  14. Alkynes • Let’s develop a general formula for alkynes • CnH2n-2 • Pull out Reference Tables… • Table P - Organic Prefixes • Table Q - homologous series & general formulas

  15. Homework • Review Book Page 197 #1-18.

  16. Let’s Keep some terms straight… • Molecular formula - represents the actual atoms in a molecule • Reminder - empirical formula is the simplest integer ratio in which atoms combine in a compound. • Structural Formula - attempts to show the kinds and numbers of atoms, but also the bonding patterns and approximate shapes • Condensed structural formulas

  17. Let’s Keep some terms straight… • Ball-and-stick model • Space-filling model (very similar to “molecular shape” model)

  18. Isomers • Get a model kit and build a ball-and-stick model of butane. • How many carbons and hydrogen did you need? • Use the same number of carbons and hydrogens, but build something different than the butane you built above.

  19. Isomers • Starting with butane there’s more than one way to combine the carbon and hydrogen atoms. • When a molecular formula can be represented by more than one structural arrangement, the compounds are called isomers of one another.

  20. Isomers • Even though they have the same molecular formula, isomers have different chemical and physical properties. • Different boiling points • Different reactivities • As the number of carbon atoms increases, so does the number of possible isomers.

  21. Naming Organic Compounds • When carbon atoms in one continuous chain, called a “straight chain” hydrocarbon • Also called “normal form” • The letter “n-” precedes the name of straight chain hydrocarbons

  22. Naming Organic Compounds • Compounds with branched chains must be given different names because they have different chemical and physical properties. • Naming rules are governed by IUPAC (International Union of Pure and Applied Chemistry)

  23. Naming Organic Compounds • Step 1 - Find the longest continuous chain of carbon atoms • The compound will be named based on its longest chain. • For example, if the longest chain is 6, then the compound will be named as a hexane.

  24. Naming Organic Compounds • Step 2 - Identify attached Alkyl Groups • An alkyl group contains one less hydrogen than an alkane with the same number of carbon atoms • Step 3 - Assign numbers to the carbon atoms in the longest chain. • They must be numbered from the end that will give the lowest number for the attached group.

  25. Naming Organic Compounds • Step 4 - Name the compound by stating the location of the attached chain, the alkyl group, then the main branch name

  26. Naming Organic Compounds • Some additional naming info… • If there is more than one of the same type of group attached to the parent chain, then a prefix is used • di- means two; tri- means three; tetra- means four • Commas are used to indicate the specific carbon to which each group is attached

  27. Naming Organic Compounds • Worksheet - Isomers of octane • Worksheet 25-4 Apply “A Compound Problem”

  28. Functional Groups • Functional Groups - are atoms or groups of atoms that replace hydrogen in a hydrocarbon, and give the compound distinctive chemical and physical properties.

  29. Organic Acids • Organic Acids are a homologous series • Functional group is carboxyl group (-COOH) • Name comes from corresponding hydrocarbon, but replace ending “-e” with “-oic acid” • Ethanoic acid (common name “acetic acid”, which is found in vinegar)

  30. Organic Acids • Most organic compounds are nonelectrolytes, but organic acids are weak electrolytes. • Reference Table R

  31. Alcohols • Alcohols - organic compounds where one hydrogen of a hydrocarbon is replaced by an -OH group (called a hydroxyl group) • The -OH group resembles the hydroxide ion, but it isn’t the same. It doesn’t form hydroxide ion in water. • Therefore, alcohols are nonelectrolytes

  32. Alcohols • The hydroxyl group is polar, though, which allows alcohols to dissolve in water. • Name by changing corresponding alkane ending “-e” to “-ol”

  33. Esters • Esters are organic compounds whose type formula is R-CO-ORI • Part comes from an organic acid, and the RI part comes from an alcohol • Esters have strong, fragrant odors.

  34. Esterification • Esterification - The organic reaction between an organic acid and an alcohol to produce an ester plus water. • Esters are named by using the alkyl name of the alcohol followed by the acid group modified to end in “-oate”.

  35. Esterification • Esterification Lab

  36. More About Alcohols • There are several different types of alcohols • Type depends on number of hydroxyl groups • Type depends on the position of each hydroxyl group on the chain

  37. Alcohols • Alcohols are primary, secondary, or tertiary based on whether the hydroxyl group is attached to a primary, secondary, or tertiary carbon atom. • Primary carbon - attached to only one other carbon atom • Secondary Carbon - attached to two other carbon atoms • Tertiary Carbon - attached to three other carbon atoms

  38. Alcohols • Primary Alcohol - has a hydroxyl group attached to primary carbon • Secondary Alcohol - hydroxyl group attached to secondary carbon • Tertiary Alcohol - hydroxy group attached to tertiary alcohol

  39. Alcohols • Monohydroxy alcohols - have one hydroxyl group • Dihydroxy alcohols - two hydroxyl groups • 1,2 ethanediol • Trihydroxy Alcohols- three hydroxyl groups • 1,2,3 propanetriol

  40. Some Practice • Page 204 #34,35, 39, 41, 42, 43,45

  41. Organic Halides (“Halocarbons”) • When a halogen (F, Cl, Br, or I) replaces a hydrogen on an alkane, the compound is called an organic halide (or halocarbon). • The functional group is the attached halogen. • Named by citing the location of the halogen attached to the chain.

  42. Ethers • Series of organic compounds in which two carbon chains are joined together by an oxygen atom bonded between two carbon atoms. • Named using alkyl group names followed by “ether”.

  43. Worksheet 26-1 Apply • Halocarbon, Alcohol, or Ether?

  44. Amines • Amines are formed when one of the hydrogens of ammonia is replaced by an alkyl group. • Named by taking the alkane name and change the ending “-e” to “-amine”, and number the alkane chain to show the location of the amine group.

  45. Carbonyl Group • When an oxygen is bound to a carbon by a double bond, it is called a carbonyl group. • Overhead “Functional Groups of Organic Compounds”

  46. Aldehydes • Aldehydes are organic compounds in which the carbonyl group is on the end carbon • Named by substituting “-al” for the final “-e” of the corresponding alkane name. • Methanal’s common name is “formaldehyde”

  47. Ketones • Ketones formed when carbonyl group is attached to an interior carbon atom that is attached to two other carbon atoms. • Named by replacing final “-e” of corresponding alkane name with “-one” • Propanone’s common name is “acetone” - nail polish remover. • Ketones are often used as solvents (because both polar and nonpolar

More Related