I've found two sources for molecular hydrogen. The photolysis of formaldehyde (See chemical formula 10 and see Novelli et al. 1999) Anthropogenic sources. While it isn't a source I think I should mention the exosphere. The exosphere is not very dense, so hydrogen (probably) doesn't react with anything. Since it is the lightest element, it probably doesn't ...


Besides man-made sources, hydrogen can be produced naturally through a process called serpentization. Mafic and ultramafic rocks, which are rich in magnesium and iron silicates, react with water to produce a variety of breakdown products summarized in the Wikipedia article on serpentine Serpentinization is a geological low-temperature metamorphic process ...


Depiction of global carbon in gigatons (Billions of tons) Origin

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