The handed molecule - Charles Stirling 1992 Christmas Lectures 3/5

Video Description

In his third lecture Charles Stirling ventures below the surface of objects at the human scale to reach the molecular level. Watch all the lectures in this series here: https://www.youtube.com/playlist?list=PLbnrZHfNEDZwZ-av1yzKu5_6pKUSVxHEm Watch our newest Christmas lectures here: https://www.youtube.com/playlist?list=PLbnrZHfNEDZyQJZLPMjwEoOLdkFBLU2m1 This was recorded on 3 Dec 1992. -- This year marks 200 years of the Royal Institution Christmas Lectures — a world famous series showcasing science, curiosity, and mind-blowing demos, and started by the legendary Michael Faraday himself. To celebrate, we're unlocking the archive. Every Saturday, we’ll upload a classic lecture to our YouTube channel — some not seen since they aired on TV. Sign up as a Science Supporter and get early access here: https://www.youtube.com/channel/UCYeF244yNGuFefuFKqxIAXw/join -- From the 1992 programme notes: In this lecture we venture below the surface of objects to reach the molecular level. We explore the assembly of molecules from atoms and show how minute they are on the scale of familiar objects. Of the roughly ten million known molecules, we shall concentrate on OH molecules such as water, alcohol, anti-freeze and sugar. Spectroscopy will show us the OH group and other groups in these tiny collections of atoms and we shall see that this class of molecule is notorious for sticking together, and we will look at the effects of this. We take up the theme of molecular handedness by way of the observation of the rotation of plane polarised light by materials. We re-enact the deduction of molecular asymmetry by Pasteur in 1847, when he solved the mystery of the multiple tartaric acids. We look at the separation of right and left handed molecules - resolution - and we look at how handed molecules associate in special ways, particularly when they contain an OH group. We shall illustrate this association with very recent work on reactions at surfaces. -- About the 1992 CHRISTMAS LECTURES We are set apart from other animals both by language and by the fact that unlike most other animals, which have mixed handedness, we are predominantly right-handed. Recent speculations have focused on the possibility that these two attributes are interconnected genetically, a link that could lead to an understanding of the neurobiology of language and its molecular biological basis. In these lectures, we shall look at first our own symmetry, in terms of handedness and our appearance, and also below the surface at our brains and other organs. Then we shall look at ourselves in the world at large, focusing on the symmetry of our fellow creatures and the artefacts that we have created. The connection of both of these to left-right relationships will be explored. The most significant handed (chiral) objects we encounter, are the molecules that we and all our surroundings are made of. We will look at the nature of these molecules and trace the understanding of the significance of handedness at the molecular level in the 19th century, for which it was the most far-reaching chemical realisation. Our contact with handed molecules has profound significance in terms of sensory perceptions such as taste and smell. We can distinguish between handed molecules and this tells us that our sensory apparatus is itself handed. Our existence depends upon the handedness of molecules both large and small and without such molecules, we would not be able to digest our food, build our bodies, or transmit our characteristics to the next generation. We return to the opening speculation. The genes - themselves composed of handed molecules - control the development of handedness and cerebral dominance, a link that has the potential to give us an understanding of the biology of language. We leave our consideration of chirality - handedness -with an unsolved mystery. Where do chiral molecules come from? Find out more about the CHRISTMAS LECTURES here: https://www.rigb.org/christmas-lectures Find out more about the CHRISTMAS LECTURES here: https://www.rigb.org/christmas-lectures --- Join this channel to get access to perks: https://www.youtube.com/channel/UCYeF244yNGuFefuFKqxIAXw/join Subscribe for regular science videos: http://bit.ly/RiSubscRibe The Ri is on Twitter: http://twitter.com/ri_science and Facebook: http://www.facebook.com/royalinstitution and TikTok: https://www.tiktok.com/@ri_science Listen to the Ri podcast: https://podcasters.spotify.com/pod/show/ri-science-podcast Donate to the RI and help us bring you more lectures: https://www.rigb.org/support-us/donate-ri Our editorial policy: https://www.rigb.org/editing-ri-talks-and-moderating-comments Subscribe for the latest science videos: http://bit.ly/RiNewsletter Product links on this page may be affiliate links which means it won't cost you any extra but we may earn a small commission if you decide to purchase through the link.