Beyond Henry's law: In nanometer-confining media, gas solubility increases widely (see figure). H2, CH4 and C2H6 solubility values in two solvents are obtained by quantitative 1H NMR spectroscopy. A mass-balance model involving the gas–liquid interface zone agrees well with the observed variation. Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2267/2008/z700638_s.pdf or from the author. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.