Some special coal sent in by a viewer! Sixth of 12 parts, each featuring chemistry gifts received by Sir Martyn during the year. All the videos in this series appear here as they're released: http://bit.ly/12_Days_Xmas CO2: https://www.youtube.com/watch?v=0dSMzg0UPPo 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://bit.ly/NottChem Periodic Videos films are by video journalist Brady Haran: http://www.bradyharan.com/ Brady's Blog: http://www.bradyharanblog.com Join Brady's mailing list for updates and extra stuff --- http://eepurl.com/YdjL9