has role has role is conjugate acid of is protonated form of gas molecular entity methane Methan CHEBI:25220 methane chebi_ontology Methane A one-carbon compound in which the carbon is attached by single bonds to four hydrogen atoms. It is a colourless, odourless, non-toxic but flammable gas (b.p. −161°C). marsh gas methyl hydride CH4 CHEBI:16183 CHEBI:14585 Methane CHEBI:6811 metano alkane methanide fossil fuel mononuclear parent hydride one-carbon compound greenhouse gas bacterial metabolite