ORGANIC CHEMISTRY DEFINITIONS

Hydrocarbon - is a compound containing carbon and hydrogen only

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

Functional group - is the part of the organic molecule that is largely responsible for the molecules’ chemical properties.

Aliphatic - carbon atoms are joined together to each other in unbranched(straight) or branched chains, or non-aromatic rings

Alicyclic - carbon atoms are joined to each other in ring (cyclic) structures, with or without branches.

Molecular formula - shows the number and type of atoms of each element present in a compound

Empirical formula - the simplest whole-number ratio of the atoms present of each elements present in a compounds

General formula - the simplest algebraic formula for any member of a homologous series

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

Structural formula - uses the smallest amount of detail necessary to show the arrangement of atoms in a molecule.

Skeletal formula - a simplified organic formula, you remove the c and h labels and any bonds to H atoms, leaving carbon skeleton and any functional groups.

Structural isomers - are compounds with the same molecular formula but different structural formulae.

Reaction mechanism - shows how a reaction takes place (showing how electrons are thought to move in a series of steps)

Curly arrow - shows the movement of a pair of electrons

Fish hook arrow - represents the movement of a single, unpaired electron (half head arrow)

Addition reaction - two reactants join together to form one product e.g alkene to alcohol.

Substitution reaction - an atom or group of atoms is replaced by a different atom or group of atoms e.g haloalkane to form alcohol

Elimination reaction - involves the removal of a small molecule from a larger one. One reactant produces 2 products. e.g elimination of water from an alcohol using an acid catalyst to form alkene.

Stereoisomers - have the same structural formula but a different arrangement of the atoms in space.

Repeat unit - is the specific arrangement of atoms in the polymer molecule that repeats over and over again, always written in square brackets.

Dehydration - any reaction in which a water molecule is removed from the starting material

Distillation - a common method used to separate a pure liquid from its impurities

Target molecule - is used to describe the compound that the chemist is attempting to prepare by organic synthesis.