Functional group
an atom or a group of atoms that form the centre of chemical activity in the molecule
Hydrocarbon
a compound containing only carbon and hydrogen atoms
Homologous series
a series of similar compounds which have the same functional group and have the same general formula, in which each member differs from the previous one by a single CH2 unit
Saturated compound
a compound in which all of the bonds between carbon atoms are single bonds
Unsaturated compound
a compound in which there is at least one double and/ triple bond between carbon atoms
Structural isomer
Compounds that have the same molecular formula but different structural formulae