N-alcanes – straight-chain (normal) alkanes (paraffins), belonging to the group of saturated hydrocarbons.
Naphtha residue/bunker oil – heavy fuel oil; used as fuel in thermal electrical power plants, power plants and industry, as well as engine fuel for big engines.
Naphthenes (cycloalkanes, cycloparaffins) – saturated cyclical components that contain only carbon and hydrogen. Cyclo-pentane and cyclo-hexane are the most simple of the naphthenes and can be found in petroleum. Naphthenes can also appear as condensates (steranes and triterpanes) and consist of multiply condensate rings with five or six carbon atoms.
Natural gas – (methane), a mixture of gaseous hydrocarbons, primarily methane (CH4) and others, up to pentane (C5H12); of mineral origin; produced from the underground by drilling and recovery through wells from reservoirs of free gas or together with oil/petroleum from oil/petroleum reservoirs; a very important raw material where energy is concerned; an ecologically acceptable energy source.