1 / 19

Alkanes, Alkenes and Alkynes 

Alkanes, Alkenes and Alkynes . SCH4U Spring 2012. Alkanes. Single covalent bonds Saturated hydrocarbons Nonpolar Not soluble in water Soluble in benzene and other non-polar solvents General formula: C n H 2n+2 (n represents the number of carbon atoms). Alkanes - Examples.

biana
Download Presentation

Alkanes, Alkenes and Alkynes 

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. Alkanes, Alkenes and Alkynes  SCH4U Spring 2012

  2. Alkanes • Single covalent bonds • Saturated hydrocarbons • Nonpolar • Not soluble in water • Soluble in benzene and other non-polar solvents • General formula: CnH2n+2 (n represents the number of carbon atoms)

  3. Alkanes- Examples

  4. Ways to represent structures e.g. C4H10 • Empirical molecular formula C4H10 • Expanded molecular formula CH3CH2CH2CH3 • Structural formula • Condensed structural formula CH3-CH2-CH2-CH3 • Line structural formula

  5. IUPAC name of organic compounds • Three basic parts: • Root: denotes the number of carbon atoms in the longest continuous chain of carbon atoms • Prefix: gives the positions and names of any branches from the main chain • Suffix: indicates the series to which the molecule belongs (e.g. –ane)

  6. Root and side group names

  7. Naming Alkanes Identify the root • Identify the longest continuous chain • Find the root for the number of carbons in the chain Identify the suffix Identify the prefix • Identify the number of carbon atoms in each side group and determine the name • If there is more than one type of side group, write their names in alphabetical order • Find the position of each side group. Numbering must begin at the end of the main chain that will give the side groups the lowest possible numbers • Use a hyphen to separate numbers and words and use a comma to separate the numbers • Use a prefix to indicate how many of each type of side group are present if there is more than one of the same side group (e.g. di-, tri-, tetra-) Name the compound

  8. Questions • Name the following molecules

  9. Drawing Alkanes • Identify the root • Identify the suffix • Draw and number the main chain, but do not add any hydrogen atoms yet • Identify the prefix and draw the side groups • Add hydrogen atoms

  10. Questions • Draw the condensed formula for • 2-methylbutane • 2,2-dimethyl-3-propyloctane • Draw the line structural formula for • 3,3,4-triethylnonane • 3,3,4,4-tetramethyldecane

  11. Physical properties of alkanes • Small alkanes are gases at standard temperature • Medium-length alkanes are liquids at standard temperature • Very large alkanes are waxy solids • The larger the alkane, the higher the boiling point

  12. Alkenes • At least one double bond in the carbon chain • At least two carbon atoms • Unsaturated hydrocarbons • Non-polar • Do not dissolve in water • General formula (one double bond): CnH2n

  13. Naming Alkenes • Identify the root • Identify the longest continuous chain that contains the double bond • Find the root for the number of carbons in the chain • Identify the suffix • Number the main chain by starting at the end of the chain nearest the double bond • If the alkene contains four or more carbons, give the position of the double bond by indicating the number of the carbon atom that precedes the double bond. The suffix consists of a hyphen, the number and -ene • Identify the prefix • Name the compound

  14. Questions • Name each alkene

  15. Questions • Draw the condensed structural formula for • 3-propylhept-2-ene • 4-ethyl-2,5-dimethyloct-3-ene • Draw a line structural formula for • 2-methylbut-1-ene • 4-ethyl-4,5-dimethylhex-1-ene

  16. Physical properties of alkenes • The first three alkenes are all gases at standard temperature • Intermediate size alkenes are liquids • Boiling points of the alkenes are slightly lower than those of the alkanes that have the same number of carbon atoms

  17. Alkynes • At least one triple bond • Unsaturated hydrocarbons • non-polar • Insoluble in water • General formula: CnH2n-2

  18. Questions • Draw the condensed structural formula for: • But-2-yne • 4-ethyl-4-methylhept-2-yne • Draw a line structural formula for • 4,5-dimethylhex-1-yne • 2,5,7-trimethylnon-3-yne

  19. Physical properties of alkynes • First few alkynes exist as gases at standard temperature • Higher boiling point than the corresponding alkanes

More Related