Instant Genius - How gases shaped life on Earth and helped human beings to prosper

Episode Date: July 18, 2024

From the oxygen in the air we breathe to the atmosphere that cloaks the Earth and protects us from the Sun’s harmful ultraviolet light, gases are essential for the existence of human beings. But did you know that we’ve also harnessed the properties of these elusive, largely invisible substances to impact almost every aspect of our lives? In this episode, we catch up with material scientist Prof Mark Miodownik to talk about his latest book, It’s a Gas: The Magnificent and Elusive Elements that Expand Our World. He tells us how gases helped us to make our cities safer and more prosperous, how Nobel Prize-winning chemistry led to the invention of neon lights and how we owe our very existence to gases influence in shaping the chemical makeup of the Earth. Learn more about your ad choices. Visit podcastchoices.com/adchoices

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you'll hear world-leading scientists and experts talking about the most fascinating ideas, in science and technology today. I'm Jason Goodyear, commissioning editor of BBC Science Focus. From the oxygen in the air we breathe to the atmosphere that cloaks the earth and protects us from the sun's harmful ultraviolet light. Gases are essential for the existence of human beings.

But did you know that we've also harnessed the properties of these elusive, largely invisible substances to impact almost every aspect of our lives? In this episode, we catch up with material scientist, Professor Mark Miodovnik, to talk about his latest book, It's a Gas, the magnificent and elusive elements that expand our world. He tells us how gases helped us to make our cities safer and more prosperous, how no gold prize-winning chemistry led to the invention of neon lights, and how we owe our very existence to gases influence in shaping the chemical makeup of the Earth.

Hi, Mark, welcome to the podcast. Thanks very much for joining us. Oh, hi. Yeah, thank you. Thanks for inviting me. Oh, you're very welcome. So today we're talking about your latest book, It's a Gas, the magnificent and elusive elements that expand our world. So let's start with a fundamental question then. What makes something a gas? Yeah, I mean, it's kind of not something people think about very often, but I mean, obviously the world's made of atoms, and there's sort of roughly 100 types of atom. And when those atoms are sort of clumped together and all bonded together, they're a solid. And when those bonds are slightly looser and they can move around, round but still be bonded together, that's a liquid. And then when they're completely free and on their own, they're a gas. And that's what a gas is. Now, gases sort of haven't got a form for that reason because the atoms or the molecules are just free to roam and off they go because they've got a certain amount of energy and they're going to go in a straight line until something hits them or

they hit something or some, you know, field interferes with what they're doing. So yeah, that's a gas. That's what it is. So can any element or substance exist as a gas? Yeah, and they do. Atoms are always pinging off surfaces. The smell, in fact, you can smell particularly liquids because they have more energy. It's all about how much energy you've got.

So if you're very, very cold as a solid or a liquid, the chances of you be able to have enough energy to basically wrench yourself away from the bonded surface is low, but it still happens. There's a vapor of everything, but it happens very, very vanishingly small. And that's why a space, of course, which is very cold, it's mostly a vacuum. It's not really much in there.

But on earth, we are surrounded by gases, and there's loads of elements in the air that we're breathing in every day. So let's stick with chemistry for a little while. So you mentioned there the states of matter, solid liquid gas. So why do different substances exist in different states at different temperatures? Yeah, well, this is all about how it's sort of this thing called thermodynamics, which is basically how things bond together and why do they go in the state they're in is to do with lowering their energy. Mostly, things adopt a low energy state, a lowest energy state they can. And the excited state, the state that's high energy is almost always the gas.

So you need a lot of energy to basically wrench yourself away from all other things. And if you've got less energy, you kind of start sticking together with things. That is sort of like the electrostatic energy of other molecules, you know, that's a bonding force that sticks you together. That's a liquid. And if you can still move around in the liquid, and they're always jostling around. It's a bit like a crowd of people, a liquid. Like it's got a sort of mobility.

It's got a dynamics. And then the solid is, you know, everyone has to sit down. If you think about like a stadium, in a way, the solid is everyone has to sit down in their seats. There's occasional few seats that are empty and you can jump into the empty seat. That means the things move around, but they only move around by that mechanism. But illiquid is more like a crowd in a street. And then a gas is like, you're just having a walk in the countryside and off you go. Great analogy.

So let's have a look at some of the details in the book then. So you kind of kick off talking about one of the most common things, you know, when we boil the kettle or whatever. That's steam. So you start off with something called the Newcomen engine. So what is that and what role does gas play in its function? Steam engines were invented very early on by the Greeks and by the Chinese, but they used steam as a gas coming out of a nozzle. So basically, if you heat water up, you'll get this gas.

It's called steam. It's invisible, actually. I know you often see a white thing, but that's actually vapor cooling from the steam. But pure steam is invisible. It's coming out. It's high energy. And it shoots out. And so that means it's like a jet.

You know, anything attached that will move forward. And so if you sort of put a pot of boiling water on some wheels, which is what they did, and you have a steam being boiled, and you have a jet, off that cart will go. And so you have a sort of very rudimentary steam engine. But it's really heavy. It runs out of fuel quite quickly. You have to keep fueling up. Also, it runs out of water very quickly, and that's also very heavy.

And it was very impractical, these early steam engines. They also got them to rotate. This one called a hero engine, it rotated. And so you think, well, okay, if we can rotate things using steam, we can grind flour, or we can pump water, hooray. But they actually had better ways of doing that. Well, we're freer. They didn't involve fuel,

which has until quite recently been a really big limiting factor on anything, like getting fuel. So they use wind. They use wind and water to do the same things. So apart from land transport, they could do lots with wind and water, like sailboats and such. Even though that's 2,000 years ago,

they had sort of steam engines. There wasn't really a sort of way in which they could get them to be useful. And then this guy newcom and comes along. And he's not the only one. They're all macking about with it in the sort of 17th century. But they start realizing that there's another way of using steam to power things. And it's sort of a subtle. It's sort of not very obvious.

But think about this. We live as 100 kilometers of atmosphere above us. So we live at the bottom of a sea of air. And that air has got gravity. It's a weight. It's pushing down on us. In fact, the weight is one kilogram per centimeter squared. So there's quite a lot of weight on our shoulders, our heads, but we're used to it because we grew up in it.

Like, that's why we have a skeleton. And so that weight is pressing down. Now, if you put steam inside a container, that weight is being pushed back by the steam. If you then seal that container and condense the steam into water, there's now a vacuum in there. But the vacuum can't push back against this massive atmospheric pressure. And so it will crush the container. And what Newcomb realized is that you don't need to. to crush the container. I mean, that's a big force. What you do is you have a piston and it basically

the vacuum, the big weight of the atmosphere above it, pushes the piston down. So you fill a cylinder with steam, you then condense it, you get a vacuum, the weight of the atmosphere pushes it down, and then you push the steam back in again, it comes up again, it goes down again, it goes up again, it goes down again. And now you have a movable cylinder basically powered by steam condensing. And it's called the atmospheric engine. And this is his big. achievement and it was very clunky and very slow but it suddenly meant that on land you could do things that you couldn't do with any other power source and it took a while about a century for that then to turn into much more efficient steam engines with loads of innovation then you get the locomotive

you get the trains you know steam engines change everything in terms of transport and they change everything in terms of manufacturing that basically the industrial age is to do with this big innovation So that can all seem quite quaint these days, you know, like we take sort of picturesque trips on steam trains or whatever for entertainment. But we still use steam to generate electricity now, don't we? Yeah, 70% of the world's electricity is still generated by steam. And that's sort of a little known fact. And why is that? Well, because actually the next generation of engines after the steam engines with these pistons were the turbine steam engines.

The steam is generated and it goes into what is. is a sort of internal turbine that looks like a sort of spiral. Think of water wheel, right? But what's flowing through it is not water, it's steam. So you're rotating something. And then as it comes out the other end, it's condensed. So you create this kind of vacuum at the end. So it pulls the steam through.

And this way of generating power through a turbine engine is an incredibly efficient way of heating up a gas using any sort of energy. So coal, oil, gas, nuclear, They all use it. So it doesn't matter whether you're generating energy by nuclear fuel or by coal or gas. You basically make energy and that is then used to make a steam. And that steam then turns it into a rotation.

And that rotation turns a generator which creates electricity. And that's how all power stations work. The only big change recently has been the growth of wind power, which is another gas power, of course. And it's on the rise, it's exciting. And solar power, which is also very dependent on gas. technology because in order to make solar panels, you basically have to create huge vacuums and control what vapor state you have in order to put them together. So yeah, we make 70% of the world's electricity by these big steam power stations and the rest of it is also

reliant on gas technologies. So let's have a look at another sort of infrastructure item that you mentioned in the book, which is lighting. So you start this off talking about Willa the Whisp's. So anyone my age will probably think of the kids' TV show at the same name. What is a Will of the Whisp? And how does that relate to gas lighting? Well, can we just go back to the TV show? Because I came back from school and I was sort of slumped in front of the TV. And in those days, there were three channels, only three.

And what was usually on for me, the only thing I would bear to watch was Willow the Whisp, which was a cartoon about a Will of the Whisp in a Marshland, so in a forest. and it's this kind of wispy ghost that gets up to no good, but you're on its side. And there's this character called Evil Edna, who's actually a TV. And so that was my first introduction to Willi Lewis. But when you go back in time hundreds of thousands of years, our ancestors lived in marshland or near marshland. And what happens in marshland is you get these mists that come in due to the weather.

And bubbling up from the marsh, it's bacterial action. They didn't know that at the time, which creates methane. and this pops up. And, okay, so methane, another invisible gas, but it happens to be flammable. It's not clear why they suddenly light. We still don't really understand that they suddenly auto-ignite, but they do. And so you're out, imagine the scene. You know, you're probably a god-fearing person.

You could pick any time in the last 10,000 years. And you're at a night and you see these lights in this kind of weird, misty landscape. And you're going to be terrified. and they were terrified. And then some people were curious and they would go towards the lights and they would then die because they would be stuck in the bog. And so these will of the whips, they have names in every culture across the world, Jack a lantern in America, you know, go to China, go to Japan.

They all have names for them. Go to Scandinavia. They're these mischievous spirits in the wood. And so there you are. Methane, this gas that we now rely on for lots of our fuel needs and the kind of Putin's war in Ukraine has really weaponized that. The gas prices went up and everyone felt it in Europe. So it's a really important gas for us. And yet, actually, it's origins in our life. Where it became important, goes all the way back to

this curiosity about these strange spirits in the woods. So when did we first get sort of gas streetlights and what impact did that have? First of all, you get a bit of chemistry. People start to work out that actually they aren't ghosts or they aren't spirits, but they're a phenomenon and a physical phenomenon. then work out that it's a mixture of gases, and that's why they pong a bit, so there's hydrogen sulfide in there. But actually, it's methane is the main constituent, and it's flammable. And then they realize that you can get methane in other processes, too. You can get it from coal, and you can get it from charcoal. And so you can make methane, and that's a big step forward. Then they're like, okay, so we take coal, which is being industrialized because of the steam revolution. So a huge

amounts of it were being dug out of the ground and transported all over the country and all over Europe in America. And so you've got coal. Now you can turn it into a gas, which is flammable, and then it becomes a realization that some inventors, it starts in Paris first, that you could take this gas and you could pump it around the city and then you ignite it on poles and you have street lighting. Now, why was that attractive as an idea? Because it's not for heat, which was the main reason, heat and cooking, that was the main need. But why would lighting be important? Well, actually cities were on the rise. There were big wealth centers, trade centers, political centres, but they were really dangerous at night. They were utterly dangerous.

And people were mugged, raped, killed. You know, it was just, you go to the wrong part of town at night. Women couldn't go out in the streets at all. It was just too dangerous. So to make city civilized required streetlights, that was the idea. It was an enlightenment idea and literally enlightening. So this gas, this one of the West was then brought in to do this. But actually to get the technology to work, it was really hard. It was explosive. It leaked. I mean, this mischievous quality of this gas was very hard to tame. And it was only actually in the UK that the kind of steam innovators was so gung-ho about this. They were really certain that, you know, Paris sort of said, oh, we're out. We don't want to do it. It's just too much hassle. It smells too

bad. But in the UK, in the early 1800s, they really went for it. And it's like showcasing a street with street lighting. And people fell in love with it. And they thought they really had this idea of the future of cities was to be these golden lit places. And it's very hard to understand that because we're so used to the ubiquity of street lighting and lights everywhere in cities. But you've got to remember, go back 200 years. They were dark, dangerous places, lit only by sort of lanterns and candles and flames. And suddenly you had a whole street at night that was gloriously lit up by this marsh gas.

And people just went for it. So they went from in the UK. There was a real kind of exuberance. It's a bit like in modern times the rise of the smartphone. It went from this novelty and what do we need smartphones for and to everyone had to have one. It's the same time period. In about 20 years in Britain, it goes from a novelty street lighting to every city over 100,000 people has these massive gas works, has piped this dangerous gas all around the city. And everyone's very proud of it.

And commerce is particularly happy because now, you know, everyone can go out at night. They can spend money. they can shop. It's an incredible vibe in the air. And then, of course, the other thing is they realize that now in people's homes, you can start using it for heating water. You can start using for heating cookie. And so it's a big revolution.

Central heating comes along. It has an enormous impact. And today, like as we said earlier, you change the price of gas and you change everything about people's lives. So let's stick with lighting. Let's have a look at neon lights. So this relies on something called a. noble gas. So what are the noble gases and how do the lights work? Yeah, so there was this conundrum.

Like, as chemistry started to develop in the 19th century and really get the hang of the fact that there are all these different elements, and they all have atomic structures that are incremental and understandable through a pattern of how many electrons, how many protons are in there, how many neutrons in there. And that determines its weight of an atom and then the amount of electrons and the way their structure on the outside determines how it reacts with things. And there's this guy called Mendeleev who makes this periodic table of all the known elements and he puts them all in these places. And he says, look, there's these patterns, these families of elements.

So lithium, potassium and sodium, they're a family. And they all have the same characteristics, but they get heavier and heavier as you go down. And it was a really big moment to chemistry. But there were spaces in this table where there were unknown elements. Like they should be there, but no one had seen them before. So off goes a whole lot of chemists looking for these elements. It's very exciting. And people start filling in the gaps.

And a guy called Lord Raleigh starts getting annoyed by the fact that some of them not quite the right weight. And he starts weighing them. And he's weighing gases, which is a hard thing to do, really carefully, spends years doing it. And he finds this anomaly. He finds this weird anomaly where there should be an extra gas, but it's not on the table. There's not a gap for it on the table. And yet he's got evidence for it.

Then a chemistry professor at UCL, my university, repeats his experiment, agrees with him. Everyone else says, you're mad. He says, no, look, there's this element. We're going to call it Argon. It should be there. But we can't find a space for it on this table of periodic elements. And it doesn't react with anything, by the way, which is another really crazy thing. Like, it's there.

It's in the air we breathe. But it doesn't do anything else just by just being there. It's just hanging in the air. And then they start correlating. This was another observation, which is the people have been looking at the sun. and look at the light from the sun and correlating the light patterns called the spectrographs and working out which elements are in the sun, and this is a technique called spectroscopy, and they could see loads of elements in the sun and map their spectrums with the ones on Earth,

and that was fine, so there was hydrogen in the sun, there was sodium in the sun, there was calcium in the sun, but there was this other element in the sun, which they couldn't ever find on Earth, and they called it helium. That also didn't belong on the table, so what is going on here? And then finally, Ramsey and Raleigh piece it together. They realize there's another family of gases, which no one had realized because they don't react with anything. So you can't see them in compounds. They're not in rocks. Well, they are in rocks, but they're sort of hidden.

And they finally unveil that there's this family of hidden Nobel gases. They're so called noble because they don't react with anything. And helium is the lightest one, and it's in the sun, but they also then find it on Earth. Argon is in the air we breathe. It's in fact 1% of the air we breathe. But again, it doesn't do anything, so no one was interested in it. The next one, the next heaviest should be this other one. And they looked for that and they tried to find it.

Finally, these beautiful techniques, UCL in the chemistry department here, made a tiny amount of it. And the way they were analyzing whether they found them or not was used this spectroscopy technique. So they basically passed electricity through it. And if you pass electricity through it, it glows. And the first time they do this, they think, it's very faint signature. and we're going to try and see what element is, but they don't get a faint sensor. They get a very bright,

what we now call neon light. And they are amazed, and they are just in wonder. And here it is, hooray, they discovered neon. It's a massive moment. Nobel Prizes follow. Everyone cheers them.

And then it's like, yeah, okay, hooray. And then people start going, well, but yeah, but they don't react with anything. They're doing anything. And this one makes an interesting colored light. But what would you do with that?

And everyone doesn't have any idea. until someone in Paris goes, you know what? It's like perfect for signs for like drinks and parties and like it just sings gloriousness. And so it becomes part of the advertising world of nightlife. So we've got street lighting and now we have these neon signs. And of course, neon now still means that, right? It still means, hey, we're open. This is a party time. That's really interesting how we go from sort of groundbreaking. Nobel Prize winning science to party time. Yeah. And then Las Vegas, of course, you know, these big party towns, New York, London, Paris, they were all lit up, all lit up with neon,

these exotic new gases that were discovered. And everyone's very excited. But they've actually filtered into a lot of our other technology now. So of course, helium is absolutely vital for healthcare. Like if you have an MRI scan, then you are relying on helium. And in fact, the price of helium's going up a lot because it's actually, there's not a lot of it on Earth, and we are very wasteful with it. Crypton, another gas is xenon, and radon, which is one of the heaviest noble gases, it's heavier than lead. It's heavier than lead, and it's a gas. That's bonkers, isn't it? Yeah. When you need to build up your team to handle the growing chaos at work, use Indeed

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name audio creates systems that deliver exceptional sound and unforgettable listening experiences at home. Try it for yourself at a focal powered by name boutique. Visit focal powered by name.com for more information. So if you mention gases to somebody, they're going to probably say the first thing, greenhouse gases. So, you know, what are they and how do they heat up the planet? Yeah, so carbon dioxide is the kind of most well-known greenhouse gas.

So we have this atmosphere 100 kilometers high approximately. It's mostly nitrogen at the moment. It hasn't always, well, it's always been a lot of nitrogen. But the composition of the atmosphere has changed throughout the history of the earth. It's got oxygen in about 19% oxygen. It's got 1% argons, which is talked about. And it's got this very tiny fraction, actually, of carbon dioxide. They're tiny.

So you have to talk about parts per million. It's around 420 parts per million. So think of a bath full of white balls and it's got a million balls in there in your bath, like if you can picture that in your head, and now drop 400 red balls in there and mix it all up. That's the concentration of carbon dioxide in the air. So it's not a lot.

But what's it doing in the atmosphere and why is it unusual? Where does it create a greenhouse effect? It's because light coming from the sun is going through the atmosphere to get to us. It hits the earth, hits us, and on a sunny day, you feel the warmth in your face. But it's also interacting with gas molecules on the way through, and some of them absorb it quite strongly, and some of them is completely invisible too. So it turns out the nitrogen doesn't absorb it, oxygen doesn't absorb it, Argo doesn't

absorb it. So the major constituents of the atmosphere don't strongly absorb the sunlight, so it gets down to the surface. But carbon dioxide does absorb it. And so it's at a wavelength for those molecules and their vibrational bonds that it's strongly absorbs. And so what that means is when it hits carbon dioxide coming through, it then will bounce around the atmosphere. And what this kind of does is it creates a sort of blanket of bouncing around light waves, heat, basically, which when it comes back off the surface is then trapped in the

Earth's atmosphere. It's not a large percentage, it's a small percentage. But the temperatures that we experience on Earth now, they are lower than historically has been in the past when carbon dioxide levels were much, much higher. I mean, they've been hugely high in the past. And the earth was very hot. And there was no ice at all because the earth was so hot. The sea levels were much higher because the earth was so hot. So we're living at a time when carbon dioxide levels have gone down. And there are other greenhouse gases too, like methane and so on. But carbon dioxide is the one that we're changing its concentration a lot by our industrial kind of processes. So that's what's happening. So 420 parts per million. Doesn't sound a lot, does it? But

But basically, you don't have to change the temperature on Earth very much for all the ice to go. And it is going. It's all melting now. And if it continues to melt, which it is doing, in fact, increasingly, then the sea levels are rising. And we know the sea level and we're measuring them. That's a fact. So the sea levels are rising. The temperature is definitely going up.

And that is all correlated to increasing calm dioxide levels, which have gone from 380 when I was a kid to 400. 20, which is now. That's like a one and a half degree rise in temperature, which we've experienced. And when the temperature goes up, another thing that happens is that it can absorb more water because hot things can basically absorb more water. So when it gets cooler in the winter, you can see condensation on your windows because, you know, the air can't absorb a lot of water when it's cold. When it's hot, it absorbs water. So guess what's happening? There's more rain. There's more flooding. There's more storms. So it's not just that the temperature is going up, is that the characteristic of how much water can be in the atmosphere is changing.

And that's then affecting us on Earth on the surface because we are having to experience a lot more water exchange. Yeah, so it's an interesting times in terms of global warming. Yeah, so let's stick with the atmosphere then. So let's move on to oxygen. So obviously this is essential for our survival. And in the book, you mentioned something called Great Oxygen Event. So what was that? And why was that so important?

If we go back to the birth of the earth in the early solar system development, it's a hot rock, it's molten, then it cools down a bit, it's very volcanic. And what's happening is it's pumping out gases from the centre of the earth, sulphur dioxide, methane, hydrogen, there's a lot of nitrogen. And if you were around then and you looked at the earth, you'd see a colour of the earth, it would be orange, It'd be a pale orange dot because of that hazy early atmosphere. So we weren't a pale blue duck, we were a pale orange dot.

This is four billion years ago. Then as it cools, the atmosphere still has got methane, has got a bit of carbon dioxide in it. It cools the water on the earth is liquid and there's a magnetic field which protects us from the solar wind, which then allows the atmosphere to remain in place. and that protects the Earth from other kind of problems, unlike Mars. So Mars also starts off with water on its surface, and it also has an atmosphere very similar,

but it doesn't have a magnetic field, and so it gets stripped of its atmosphere. That means that all of the water evaporates into the solar system, and it's a hard, barren rock. But that doesn't happen to Earth. So we maintain our atmosphere, which is really important. And then, for some reason, no one knows how. At the bottom of the sea, we think, using some of the energy from the volcanic, some self-organizing chemistry happens and little cells start, well, life, tiny bacteria form and they are feeding not off the solar sun, they are just feeding off energy from the earth.

So there's no oxygen around at all, right? There's no, hardly any tiny amount. And then what happens is that 2.5 billion leaseations, some sort of mutation and these cyanobacteria learn how to take sunlight and turn that with carbon dioxide and material. tabalize that. They don't have to sit at the bottom of the sea near events. They can be everywhere. And they just take over. They take in carbon dioxide with sunlight and they breathe out oxygen. And this oxygen, free oxygen, I mean, it's an incredibly powerful molecule oxygen. It's incredibly reactive. So first of all, it just reacts with all the iron in the ocean. So it's bubbling around. And of course, that's all the sediments. You see when you go to the seaside, you see these big iron

sediments, all the iron oxide, all the stuff. That's all formed then. And then, and then, after a while, there's no more iron to react. So it starts bubbling into the atmosphere. And now the atmosphere becomes oxygen rich. And if you were an alien looking down at that orange dot, you'd think, okay, there's life coming there. Because it's very, very unusual to have free oxygen, because oxygen is so reactive.

It would either just all react or it has to be continuously produced. And if it's being continuously produced, it's likely to be life. This oxygen is so reactive. There's a mass extinction. But the ones that survive, learn how to deal with oxygen. and they start having these antioxidant kind of processes. Until you get these symbiotic thing, you've got some cells that rely on oxygen to build themselves,

and they become oxygen users. And then nothing happens for a long time until another billion years goes by, and you get this big explosion of a complex cell that's using oxygen, and it's using oxygen to fuel itself, and it's a complex eucarriot. It's got these nucleus in them.

And that is a big step forward in life. And then the oxygen levels go up again, And then suddenly you get plants, fungi, animals, first of all being generated in the seas, then coming onto the land. And that's the kind of world that we would now recognize where oxygen is now a proportion of the atmosphere like 20%. In fact, it goes up to 35%, we think. So, yeah, we're used to living in this oxygen-rich environment, but it's actually a relatively recent thing. And it fuels our bodies. Obviously, we have to have it.

We can't survive a few seconds without it. But there's a growing body of evidence and thought that it's the fact that oxygen is what we use to metabolize that makes big organisms possible. Because otherwise, you just need access to a lot of energy to basically run a big organism. And so it's the rise of oxygen in the atmosphere that is what makes us, big, big organisms, us, trees, plants possible. And you might think, okay, what do you mean about plants? They give out oxygen. They don't take it in, but they do. plants also breathe oxygen and their roots breathe oxygen.

So we're all here thanks to gas. Oh, we're definitely all here thanks to get. In fact, it's our life support system. I mean, literally our life support system. And you know that if you go to hospital, of course, but all you have a choke, you realize you've got a minute or two without gas and then you're done. But it's also our life support system in so many other ways.

It's our psychological life support system. It's our technological life support system in terms of generating our electricity, you know, allowing us to fly, to drive, to ride a bicycle. It's our life support system in terms of our musical instruments. You sound is a vibration in the air. Controlling that is such a beautiful thing, such a joyous thing. And we've spent a lot of time in history working out how to make different instruments and to sing.

The smell, our sense of smell, is a gas technology, if you like. And without that, you know, a lot of our emotional attachments to things and our ability to navigate the world and our emotional world and our attachments to people and home, they all disappear. So yeah, gas is something important. Thank you for listening to this episode of Instant Genius, brought to you from the team behind BBC Science Focus. That was Professor Mark Miodovnik.

To discover more about the topics we've just discussed, check out his latest book, It's a Gas, the magnificent and elusive elements that expand our world. If you liked what you just heard, then please do consider subscribing to Instant Genius on your preferred podcast platform. The current issue of BBC Science Focus magazine is out now. Pick up a copy wherever you buy your favourite magazines

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