Uploaded March 2026 | Updated September 2026, 3 weeks ago
Watch Peter Wothers, the modern alchemist, as he unpicks the chemistry of the world around us - looking at air, water and earth - three of the original ancient Greek 'elements' that tantalised alchemists for centuries.
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Take a deep breath. Inside your lungs is a mixture of highly reactive and incredibly stable gases. Oxygen is the most reactive constituent. When we eat it's these O2 molecules that seize electrons from our food to give our bodies the energy to live. Add a third oxygen atom and we make ozone, a gas so reactive that it's toxic if we breathe it in, but high up in the stratosphere this gas protects us from the sun's radiation. Add a carbon atom and we produce carbon dioxide, a greenhouse gas responsible for warming the planet.
Nitrogen, the most common element in air, is an unreactive gas, but a key atom in every cell in every living thing on Earth. How can we imitate nature to bring this suffocating gas alive?
Even less reactive are the Noble or inert gases. They're so stable they are the only elements that exist naturally as individual atoms – but what is it about them that make them so inert? And how can we excite these gases enough to join the chemical party?
We've come a long way from the days when alchemists thought the air was a single element, as we unravel the puzzle of how and why these compounds of oxygen hold the key to the viability of life on the planet.
About the 2012 CHRISTMAS LECTURES
When medieval alchemists staged spectacular stunts in front of royalty they never revealed the secrets of their mystical potions and fire-breathing creations. Today's chemists can perform equally impressive feats, but they do so to explain and explore the extreme frontiers of our material world.
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Join this channel to get access to perks:
youtube.com/channel/UCYeF244yNGuFefuFKqxIAXw/join
Subscribe for regular science videos: bit.ly/RiSubscRibe
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Chapters 👇
00:00 Intro: Alchemists vs Modern Chemistry 🔥
02:20 What Is Air Really Made Of?
04:00 Crushing a Steel Drum with Air Pressure
07:10 The Real Composition of Air
12:30 The Periodic Table Comes to Life
16:40 Inside the Atom: Protons, Electrons & Identity
21:30 Why Carbon Forms Millions of Compounds (Diamond Demo 💎)
26:00 Phosphorus: The Element Discovered from Urine 💡
30:00 Noble Gases Explained
35:30 Xenon, Anaesthesia & Saving a Life
41:30 Liquid Oxygen + Cereal Explosion 🔥
50:30 Nitroglycerin, Airbags & Lightning ⚡
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The Ri is on Twitter/X: twitter.com/ri_science
and Facebook: facebook.com/royalinstitution
and TikTok: tiktok.com/@ri_science
Listen to the Ri podcast: podcasters.spotify.com/pod/show/ri-science-podcast
Donate to the RI and help us bring you more lectures: rigb.org/support-us/donate-ri
Our editorial policy: rigb.org/editing-ri-talks-and-moderating-comments
Subscribe for the latest science videos: 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.
Watch Peter Wothers, the modern alchemist, as he unpicks the chemistry of the world around us - looking at air, water and earth - three of the original ancient Greek 'elements' that tantalised alchemists for centuries.
---
Take a deep breath. Inside your lungs is a mixture of highly reactive and incredibly stable gases. Oxygen is the most reactive constituent. When we eat it's these O2 molecules that seize electrons from our food to give our bodies the energy to live. Add a third oxygen atom and we make ozone, a gas so reactive that it's toxic if we breathe it in, but high up in the stratosphere this gas protects us from the sun's radiation. Add a carbon atom and we produce carbon dioxide, a greenhouse gas responsible for warming the planet.
Nitrogen, the most common element in air, is an unreactive gas, but a key atom in every cell in every living thing on Earth. How can we imitate nature to bring this suffocating gas alive?
Even less reactive are the Noble or inert gases. They're so stable they are the only elements that exist naturally as individual atoms – but what is it about them that make them so inert? And how can we excite these gases enough to join the chemical party?
We've come a long way from the days when alchemists thought the air was a single element, as we unravel the puzzle of how and why these compounds of oxygen hold the key to the viability of life on the planet.
About the 2012 CHRISTMAS LECTURES
When medieval alchemists staged spectacular stunts in front of royalty they never revealed the secrets of their mystical potions and fire-breathing creations. Today's chemists can perform equally impressive feats, but they do so to explain and explore the extreme frontiers of our material world.
---
Join this channel to get access to perks:
youtube.com/channel/UCYeF244yNGuFefuFKqxIAXw/join
Subscribe for regular science videos: bit.ly/RiSubscRibe
---
Chapters 👇
00:00 Intro: Alchemists vs Modern Chemistry 🔥
02:20 What Is Air Really Made Of?
04:00 Crushing a Steel Drum with Air Pressure
07:10 The Real Composition of Air
12:30 The Periodic Table Comes to Life
16:40 Inside the Atom: Protons, Electrons & Identity
21:30 Why Carbon Forms Millions of Compounds (Diamond Demo 💎)
26:00 Phosphorus: The Element Discovered from Urine 💡
30:00 Noble Gases Explained
35:30 Xenon, Anaesthesia & Saving a Life
41:30 Liquid Oxygen + Cereal Explosion 🔥
50:30 Nitroglycerin, Airbags & Lightning ⚡
---
The Ri is on Twitter/X: twitter.com/ri_science
and Facebook: facebook.com/royalinstitution
and TikTok: tiktok.com/@ri_science
Listen to the Ri podcast: podcasters.spotify.com/pod/show/ri-science-podcast
Donate to the RI and help us bring you more lectures: rigb.org/support-us/donate-ri
Our editorial policy: rigb.org/editing-ri-talks-and-moderating-comments
Subscribe for the latest science videos: 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.
