A laboratory analyses an alkane found in a fuel sample. Each molecule of the alkane contains eight carbon atoms. The general formula of the alkanes is CnH2n+2\text{C}_n\text{H}_{2n+2}CnH2n+2.
Which formula should the laboratory record for the alkane?
C8H17\text{C}_8\text{H}_{17}C8H17
C8H16\text{C}_8\text{H}_{16}C8H16
C8H20\text{C}_8\text{H}_{20}C8H20
C8H18\text{C}_8\text{H}_{18}C8H18