Mercaptans - or Thiols - are some of the smelliest chemicals around. We didn't dare open the bottle. PsyFile: null More chemistry at http://www.periodicvideos.com/ Follow us on Facebook at http://www.facebook.com/periodicvideos And on Twitter at http://twitter.com/periodicvideos From the School of Chemistry at The University of Nottingham: http://www.nottingham.ac.uk/chemistry/index.aspx Periodic Videos films are by video journalist Brady Haran: http://www.bradyharan.com/ Brady's other channels include: null (Psychology stuff) null (Physics and astronomy) null (Numbers and maths) null (Space stuff) null (Science and behind the scenes) null (Food science) null (Big science facilities) null (Favourite scientists) null (Academic look at the Bible) null (Modern language and culture) null (Philosophy stuff)