Organic chemistry

• Carbon


  Has the ability to mix and rearrange the four orbitals in the outer shell
• Hybridization


  The property of carbon to mix and rearrange the four orbitals in the outer shell
• organic compounds with the same chemical activity but different physical properties are known as homologous series
• carbon has the ability to form straight chained compounds, rings and branched chain compounds this process is called catenation
• carbon compounds can be: aromati
• carbon compounds can be aromatic eg. benzene aliphatic and alicyclic
• Carbon is tetravalent which means it has four electrons on its outermost shell that are available for covalent bonding
• When butene was analyzed it was found to contain 85.72% carbon and 14.28% hydrogen. To calculate its empirical formula, the following steps are done:

  Element

  Percentage Divide by atomic mass Divide by smaller ratio Empirical formula is CH2.

  C

  85.72 % 85.72/ 12 = 7.14 7.14/7.14= 1

  H

  14.28 % 14.28/1 = 14.28 14.28/7.14 = 2
• The molecular formula shows the actual number of each kind of atom in a molecule.
• Empirical formula is the simplest whole number ratio showing the atoms that combine to form a compound.
• n x empirical formula mass = molar mass n x 13g = 78g n = 78g / 13g = 6

  Molecular formula = 6 x (CH) = C6Hg.
• The structural formula shows the bonds in the molecule
• displayed formula is where all the bonds are clearly shown with the location of the atoms.
• Condensed structural formula which shows the placement of atoms in the molecule. For example

  CH3(CH2)CH3 and CH3CH2OH

  Propane ethanol
• Alkanes are described as aliphatic or alicyclic compounds. Aliphatic compounds are those organic compounds with straight or branched chains while alicyclic compounds contain rings of carbon atoms.
• Alkenes with four or more carbon atoms can display structural isomerism. For example
• The position of the first unsaturated carbon must be given in the name, that is to say the position of the double bond must be specified. Pent-l-ene
• When more than one hydroxyl groups are present, the position must be stated. For example,

  ethane-1,2-diol
• In phenol, the hydroxyl (OH) group is attached directly to the benzene ring and the compounds are named as in the naming of aromatic compounds
• Aryl groups are derived from benzene or from a benzene derivative by removing a hydrogen atom that is bonded to the benzene ring. The radical from benzene is called “phenyl” and is used to identify the -C6H5 group example CH3OH

  Phenylmethanol Phenylamine NH2
• Groups in the 2 and 6 positions are said to be in the “ortho” positions while groups in the 3 and 5 positions are said to be in the “meta” positions. The 4th carbon atom is the “para” position.
• Compounds that have the carbon-oxygen double bond (C=0) or the carbonyl group are called carbonyl compounds.
• Aldehydes have at least one hydrogen atom attached to the carbonyl carbon atom while ketones have two R-groups (aliphatic or aromatic) attached.
• in carboxylic acid the ending ‘ane’ is replaced by ‘anoic acid’. The carbon atom in the COOH is always given the number one position.