Chapter 11

• What is a hydrocarbon? (including saturated and unsaturated)


  -A hydrocarbon is a compound containing carbon and hydrogen only.

  
  

  -Hydrocarbons can be saturated or unsaturated.

  
  

  -A saturated hydrocarbon has single bonds only.

  
  

  -An unsaturated hydrocarbon contains carbon-to-carbon multiple bonds.
• What is a homologous series?

  -A homologous series is a family of compounds with similar chemical properties whose successive members differ by the addition of a -CH2- group.

  
  

  -The simplest homologous series is the alkanes. Alkanes contain single carbon-to-carbon bonds.
• What is a functional group?

  -A functional group is the part of the organic molecule that is largely responsible for the molecule's CHEMICAL PROPERTIES
• What can hydrocarbons be classified as?


  -Aliphatic - carbon atoms are joined to each other in unbranched or branched chains.

  
  

  -Alicyclic - carbon atoms are joined to each other in ring (cyclic) structures.

  
  

  -Aromatic - some or all of the carbon atoms are found in a benzene ring.
• Name three homologous series of aliphatic hydrocarbons.


  -Alkanes - single carbon-to-carbon bonds.

  
  

  -Alkenes - at least one double carbon-to-carbon bond.

  
  

  -Alkynes - at least one triple carbon-to-carbon bond.
• What are side chains attached to the parent chains called?


  -Alkyl groups.
• What prefix is used for naming cyclic alkanes?


  -Cyclo
• Different functional groups.


  -Alcohol - OH - hydroxy- - -ol

  -Haloalkane - -Cl, - Br, -I - chloro-, bromo-, iodo-

  -Aldehyde - -CHO - -al

  -Ketone - C(CO)C - -one

  -Carboxylic acid - COOH - -oic acid.

  -Ester - COOC - oate

  -Acyl Chloride -COCl - oyl chloride

  - Amine - NH2 - amino (prefix) or amine (suffix)

  -Nitrile - CN - Nitrile
• What is the molecular formula?


  -The molecular formula shows the number and type of atoms present in a molecule.

  
  

  -It does not show how the atoms are joined together and different molecules can have the same molecular formula.
• What is the empirical formula?


  -The empirical formula is the simplest whole-number ratio of the atoms of each element present in a compound.
• What is the general formula?


  -The general formula is the simplest algebraic formula for any member of a homologous series.
• What is the displayed formula?


  -The displayed formula shows the relative positioning of all the atoms in a molecule and the bonds between them.

  
• What is the structural formula?


  -The structural formula uses the smallest amount of detail necessary to show the ARRANGEMENT OF ATOMS IN A MOLECULE

  
  

  -e.g. CH3CH2CH2CH3
• What is the skeletal formula?


  -A skeletal formula is a simplified organic formula. You remove all of the hydrogen and carbon labels from carbon chains and any bonds to hydrogen atoms.

  
  

  -This leaves just a carbon skeleton and any functional groups.

  
  

  -A line represents a single bond.

  
  

  -An intersection of two lines represents a carbon atom.

  
  

  -The end of a line represents a -CH3 group.

  
  

  - Group that are not CH's require a bond to show their presence : e.g. the OH is directly off the carbon

  
• What are structural isomers?


  -Structural isomers are compounds with the same molecular formula but different structural formulae.
• Isomers with the same functional group.


  -In compounds containing a functional group, the functional group can be at different positions along the carbon chain.
• Isomers with different functional groups.


  -Sometimes two molecules containing different functional groups have the same molecular formula.

  
  

  -Aldehydes and Ketones with the same number of carbon atoms have the same molecular formulae.
• How can covalent bonds be broken?


  -By homolytic fission or heterolytic fission.
• What is homolytic fission?


  -When a covalent bond breaks by homolytic fission, each of the bonded atoms takes one of the shared pair of electrons from the bond.

  
  

  -Each atom now has a single unpaired electron.

  
  

  -An atom or groups of atoms with an unpaired electron is called a radical.
• What is heterolytic fission?


  -When a covalent bond breaks by heterolytic fission, one of the bonded atoms takes both of the electrons from the bond.

  
  

  -The atom that takes both electrons becomes a negative ion.

  
  

  -The atom that does not take the electrons becomes a positive ion.
• Organic reaction mechanisms.


  -An equation tells you about the reactants, products and stoichiometry of a reaction, but it does not provide any information about how the reaction takes place. This process is known as the reaction mechanism.
• What are the types of reaction?


  -Addition - In an addition reaction, two reactants join together to form one product.

  
  

  -Substitution - In a substitution reaction, an atom or group of atoms is replaced by a different atom or group of atoms.

  
  

  -Elimination - An elimination reaction involves the removal of a small molecule from a larger one. In an elimination reaction, one reactant molecule forms two products.
• Why is carbon often found in organic compounds?


  Its ability to form 4 covalent bonds
• Example of homolytic fission


  H3C - H3C -> H3C+CH3 (*represent radicals)
• Example of hetrolytic fission


  Cl - H3C -> H3C+ + Cl-
• What do curly arrows represent?


  Curly arrows are used to show the movement of electron pairs when bonds are being broken or made.

  
  

  USE HALF ARROWS FOR HOMOLYTIC FISSION
• why is carbon so special?

  has 4 valence electrons to form 4 strong covalent bonds to other atoms
• what is a hydrocarbon?


  a compound made of hydrogen and carbon atoms only
• what does saturated mean?


  has single bonds only
• what does unsaturated mean?


  has at least one double or triple bond
• what does homologous series mean?


  a family of compounds with similar chemical properties whose successive members differ by the addition of -CH2 group
• what does functional group mean?


  the part of the organic molecule that is largely responsible for the molecule's chemical properties
• what do aliphatic hydrocarbons look like?


  carbons are joined to each other in unbranched or branched chains, or non-aromatic rings
• what do alicyclic hydrocarbons look like?

  carbons are joined to each other in ring (cyclic) structures, with or without branches
• what do aromatic hydrocarbons look like?


  some or all of the carbon atoms are found in a benzene ring
• alkanes vs alkenes vs alkynes


  alkanes - only have single carbon-carbon bonds

  alkenes - have at least one double carbon-carbon bond

  alkynes - have at least one triple carbon-carbon bond
• what is the functional group and suffix of alkenes?


  functional group: C=C

  suffix: ene
• what is the functional group and suffix of alcohols?


  functional group: -OH

  suffix: ol
• what is the functional group and suffix of haloalkanes?


  functional group: -Cl, -Br, -I

  prefix: chloro-, bromo-, iodo
• what is the functional group and suffix of aldehydes?


  functional group: -CHO

  suffix: -al