methane vs alkane

methane and alkane both are nouns.

Word	Noun	Adjective	Verb	Adverb
methane	Yes	No	No	No
alkane	Yes	No	No	No

As nouns, alkane is a hypernym of methane; that is, alkane is a word with a broader meaning than methane:

methane: a colorless odorless gas used as a fuel
alkane: a series of non-aromatic saturated hydrocarbons with the general formula CnH(2n+2)

Other hypernyms of methane include gas, alkane series, methane series, paraffin, paraffin series.

methane (noun)	alkane (noun)
a colorless odorless gas used as a fuel	a series of non-aromatic saturated hydrocarbons with the general formula CnH(2n+2)