Representing the formulae of organic compounds

• Molecular formula shows the number and type of atoms of each element present in a molecule.
• Empirical formula is the simplest whole-number ratio of the atoms of each element present in a compound.
• General formula is the simplest algebraic formula for any member of a homologous series.
• Displayed formula shows the relative positioning of all the atoms in a molecule and the bonds between them.
• Structural formula uses the smallest amount of detail necessary to show the arrangement of the atoms in a molecule.
• Skeletal formula is a simplified organic formula. You remove:

  • all the carbon and hydrogen labels from your carbon chains
  • any bonds to hydrogen atoms

  This leaves just a carbon skeleton and any functional groups. In skeletal formulae:

  • a line represents a single bond
  • an intersection of two lines represents a carbon atom
  • the end of a line represents a CH3 group