Introduction to organic chemistry

• Structural isomers are compounds with the same molecular formula but a different structural formula
• Stereoisomer are compounds with the same structural formula but a different arrangement of atomic in a space
• Hydrocarbons contain only carbon and hydrogen
• Saturated hydrocarbons contain single carbon-carbon bonds only
• unsaturated hydrocarbons contain one or more carbon-carbon double bonds
• Homologous series is a family of organic compounds with contain the same functional group and have the same formula but a different carbon chain length, with each successive member differing by CH2
• Functional group is an atom or group of atoms that give organic compounds its particular chemical properties
• Test for alkenes:

  Add bromine water and shake

  Positive test will be if the bromine water decolourises
• Test for halogenoalkanes:

  The halogenoalkane is mixed with sodium hydroxide solution and a small amount of silver nitrate containing nitric acid is added Into a water bath at 60 degrees.

  Chloroethane - white ppt

  Bromoethane - cream ppt

  Iodoethane - yellow ppt
• Test for alcohols:

  Add sodium metal - effervescence is observed if positive

  or

  Add acidified potassium dichromate - it will turn from orange to green if positive
• Test for Aldehydes:

  Add acidified potassium dichromate - will turn orange to green

  or

  Tollens reagent - silver mirror

  or

  Fehlings solution - will form a brick red precipitate
• Test for Carboxylic acids:

  Litmus paper - will turn red

  Sodium - effervescence
• Chain isomers have the same molecular formula but the hydrocarbon chain is arranged differently
• Position isomers has the same functional group but it a different position
• Functional group isomers have the same molecular formula but a different functional group