Q&A: Delightful and Dangerous Liquids - with Mark Miodownik

[Music] do you by any chance have a fear of flying I I have this weird okay when I was writing this book I obviously got very sensitized to all these issues and I start to sort of think about them a lot and I um I realized that I always think I'm going to die but I it's not a fear of flying it's kind of like I just I just I just I'm convinced that I will be the exception I don't know why that is anyway I started talking about this to people I thought you know I I always have this feeling like I even know I know little facts and I'm involved with all the people who designed these things I've seen the tests and I seen the data I still feel like that and they say oh yeah we feel like they're - yeah yeah yeah we feel like that in fact every time I sit down I look around me and I see who's got fast shoes on and I and it's amazing the number of people who I think must be a psychological thing who kind of mapped their exit so yeah I don't I am yeah I'm not Freya Freya but I sort of feel like this kind of reflection on death always comes over me even if it's short hops light died chemistry teacher I thoroughly enjoyed this is just throw the clock back it's brilliant now my question is you mentioned about the slaughter the mass slaughter of sperm whales to keep people illuminated in the evenings are there any stats that tell us about the recovery of whales after Thomas Edison discovered the light bulb um well yeah I don't know about Edison because actually what happens is kerosene saves the whales partly because of the Civil War of America American Civil War and what happens is that some a lot of the boats get grounded by that and so the whaling ships get get grounded at Harbor and that allows the early people who are trying to sell this much more it's more expensive than whale oil kerosene it allows them a few years to get the industry off the ground and once they're off the ground and they start rank cranking it up they by the time the civil war's over they are dominant so it's it's kerosene that saves the whale rather than Edison who then comes later and of course in between that is gas lighting as well so there's a few other things that happen between between this and and and this alternate century and Edison great talk thanks what's I don't know if you've seen its YouTube of course there's this sort of cornflour e-liquid thing that people couldn't consider and pick up and stuff and then next minute they hit it with a hammer and it breaks the hammer well what what's going on there it's it's a type of liquid that's called a non-newtonian liquid and that means that so with water if you if you put more pressure on it it flows faster and that's that's a Newtonian liquid sorry oh it's a liquid problem another like sorry okay if you pour liquid wines another Newtonian liquid so liquids are Newtonian often but some are not so basically when you when you push them harder you know put a bigger force on them instead of flowing faster they they actually become more viscous and they sort of freeze up and the other way round is also true you can get some that become runya so when you've ever done painting and decorating they'll say you get the the pot of paint emulsion and you open it it says stall it says for stir it vigorously and it's like a jelly when you get it you stir it so you put it under some stress and it becomes all running right so that's non-newtonian you then that allows you to put it onto the brush and onto the onto your wall and then because there's no stress on it it then becomes vistas again so you get a thick coat so actually the whole emulsion thing is that is an example of that that's that you buy and when you if you ever are decorating and you you think I'm not gonna buy the expensive one this is one of those cases where the expensive one is going to is going to do you a lot better because they've put spent more time on the chemistry of making that transition between hibiscus and more stable and they will get a thicker Co and you will have to paint less but there are many other examples like you know quicksand I think places you know which appear solid under certain circumstances but then you will sink into them and if you try and pull someone out of your quicksand it all becomes viscous and hardens up around them and you won't be able to escape yourself from concretes and because of its non-newtonian qualities and and then the last example is that by rows so ink is non-newtonian and that's why has how by rows work they they flow down into the nib and then as a result of the sheer force of rolling they'd come thin and they and they and they cover nicely and then they immediately set so they don't run so it gets into lots of different parts of chemistry non-newtonian behavior from this this side subject on the end over here keep your hand up into a microphone comes alone thanks you mentioned how we're gonna need to find alternatives to kerosene for plane fueled do you have any ideas about alternatives that are greener yeah so on the one hand you could say we should keep using liquid fuels because they are some energy dense if you try and go to a at the moment a lot of people trying to go to batteries but batteries energy per weight and of course you're taking off means that energy per weight is a really big deal but it's also true of cars so that that ratio how much energy you go out but how much weight it is it's really poor for battery even lithium batteries that are the state of the art a liquid a liquid fuel is a hundred times better so if you go away from liquids the batteries you you you it's really difficult to see a way in which we're going to be able to fly to America for instance at the moment there's still absolutely no question we can do it for current battery technology so the question well is there a more sustainable liquid that is like kerosene but isn't contributing to global warming well of course we could use plant fuels so so-called biodiesel or bio kerosene you can make the same things because actually that's where that oil came from right organisms and in fact the economy that uses this the most is Brazil right Brazil doesn't use petroleum it uses alcohol which it makes from sugarcane and that has that in its trucks and its cars but it's not oh so that we in this some ways you might say we're great will just grow our fuel and then we'll be done it's a slight caveat there which is that it's not it takes a long time for the carbon in the atmosphere to get back into the plants so so potentially we're kind of we still have to sort it we still we even do we switch today we'd still have to sort out the carbon that's in the air and the other problem is that a huge amount of very of the crops land if we would try and fuel everything from crops now we wouldn't have any food cuz you won't have any land oh boy so you'd have to you'd have to trade off fuel with food I'm gonna grow wheat for bread or write a rice or I'm gonna grow kerosene and it's it when you do the calculations it seems there's not enough land to do both so that so it's a complicated thing and yeah that's why it needs some fresh thinking from people like you I think brilliant talk thank you what's wrong with liquid soap right well I know how you don't like meat there but basically I mean first of all when you squeeze this into your hands I mean am I alone in thinking that essentially that feels like it when you pick up your friends pet hamster in it wheeze itself it's a little tiny alert something anyway that's number one but it's a more fundamental dislike which is that you do that right squirt and then if you're good you do this but no you're not good mostly cuz you're in a hurry or whatever yeah you go that you go under the tap at this point squirt under the tap and then what happens is most of that liquid soap goes straight down the non-sync and and and this is a fact that has been studied like only 10 percent of the active ingredients actually ends up cleaning anyone's hands because of that problem and the other thing I really find frustrating about liquid soap is that the active ingredient is this thing called sodium laureth sulfate and you'll see this in its core if you look on the back of your shampoos of almost any of your liquid cleaning pot you will see this if you look in your toothpaste you'll see this and this is this is the go-to detergent for any salt cleaning action it's incredibly powerful and it doesn't create a scum that's one thing so you don't get that frothy scum even in hard water so people like it like that it's but the the way of making sodium laureth sulfate the default way of getting it is to get palm oil from the tropics and palm oil right palm oil this you know this is the problem we were just talking about which is that it's become a crop that's so valuable because of the growth of liquid soap that's and other things that it it's you know it's displacing whole habitats and because as we keep buying this stuff so that that market keeps growing and the money talks so if we if we if we could row back on our consumption of these types of molecules then we would be saying a very strong message economic message which is that a bar soap was wrong with a bar of soap we can make it sustainably and locally here and I think those sort of environmental concerns are going to grow the best there is a different product that's sort of based on the same port and you see an airports amazingly which is a foam dispenser and what's great about foam dispensers is actually you only need a tiny bit of this stuff if it dispenses a foam you're not it most of it's not going down the sink so it's a better way of dealing with the liquid say so you'll want a liquid soap go for a foam dispenser or a bar but don't sit so gas or solid but don't go I mean the foam is a gas wait but don't go in the middle anyway every time I say every time I'm sorry it's the hamster anyway why are you only to take a hundred me hundred mils on a pain good question and I forgot to address that thank you so when this whole thing came at parent and people realized that actually you could blow up a plane in fact someone did try and blow up a plane and it was filed by bringing nitroglycerine on board they started to do some experiments about how much liquid nitrogen you needed to blow up a plane so imagine you took this amount on and then you kind of exploded it and because it's got all the oxygen in there needs it's gonna go boom would it would it take the plane down and they worked out the hundred milliliters would cause damage but it wouldn't blow the plane up so they said okay you can't take more of it so that means that even if you have liquid not nitroglycerine and and the problem is that they don't they find it very difficult to distinguishing nitroglycerine and peanut butter for instance and you think that's collude Icarus you can easily tell difference but it's not so easy they have very similar chemical compositions and so even you do a chemical analysis it's not that easy and you have to do it fast an airport that you have to get people through you have to get three people through a thousand an hour so it's not just be gonna do it in a lab and you're yeah that's definitely peanut butter no it's like you know it's like can you do it once every ten seconds and that's what's causing trouble but you can see the floor I don't want to alarm people unnecessarily but you can see the floor in this limit con you take ten and then mix them all together nothing stopping you doing that unfortunately it's theater I mean most of most of security is theater as I was alluding to but is still the safest form of long distance travel yes fascinating lecture thank you um you touch briefly upon how alcohol wreaks havoc in the human body because of its so-called OAH functional group but obviously everyone gets told that drinking alcohol is bad for us but very few people actually heed that advice can you think you could elaborate on how alcohol actually wreaks havoc in our bodies yeah yeah okay so essentially your body tries to decompose it I mean basically into interface it gets straight into your bloodstream via the carbon so it so even when you're drinking the sit actually quite a lot of the alcohol is still already going into your bloodstream because there's a lot of there's a lot of them blood vessels very close to the surface so it goes through the membranes as a small molecule goes through the membranes go straight it's that's why you get that's why you immediately feel a bit of a hit then it goes into your stomach and the rest of it comes through into your stomach you you you can your body has the ability to kind of digest it and get rid of its toxicity but it can only do so about one glass an hour and so the more you do that drink them essentially the more you've got in your blood that it's not being able to kind of decompose then if if it's in your belly gets your brain and there interferes with different nerve and neurotransmitters and you get all sorts of different effects depending on your person your physiology in your age but essentially it kind of is a depressant so it's sort of depresses your system if you're nervous and you're and you're worried then of course it will depress those nerves and worries so that's often why people like it but it also depresses your ability to do actions and to you know use your muscles which is why you come incapacitated if you drink too much so yeah so the other thing to say about it is that you can make it yourself obviously but if you distill your own alcohol the first a bit like with the fuel the first fraction that comes off so if you're making hooch or you know homemade whiskey or vodka or any protein or any things when you're doing the distillery the first fraction comes off is the light fraction and that's methanol now methanol is really poison it's like we thought the alcohol is called ethanol it's got two carbons but methanol is got one carbon and that completely will attack your optic nerves and all sorts of things and that's where the phrase bright blind drunk comes from so people who used to distill own alcohol but then forget to get rid of their methanol we just go blind and people still die today making their own alcohol but also people die by drinking because when you go through duty-free a lot of the perfumes that's all alcohol because that that's the substance in which that the fragrances are dissolved and and and floor cleaner is alcohol but cheap ones don't get rid of the methanol and people drink it because it's cheap way of getting drunk and then they die of methanol poisoning so so however bad ethanol is on your system it's actually recoverable mostly it doesn't it does attack your liver but methanol is the real dangerous one someone can pass the microphone along that'd be great just wait for it to come to you thanks Lou is yours you know gu6 yeah mr. blue beside a glue stick a solid or liquid so it's a it's a plastic essentially that you heat up until might glue stick glue gun glue sticks right oh sorry sorry yeah pretty thick yeah okay so glues so so yeah so now you're into what's a liquid and the definition of a liquid you're sort of thinking must be obvious there's solid liquid gas how difficult can it be but then there's kind of yeah there's sort of putties and there's pastes and you know there are things that mmm it's a putty or a paces out a liquid or as a solid it sort of got of some solid qualities and some liquid qualities and when you tore drill down further you realize that this definition solid liquid is is really only applicable to pure elements that actually soon as you get into the kind of real world of glues or you know cements or the tar on the road that we talked about before that's a liquid it flows and then you're okay so is that the definition of liquid liquid flows oh no but nobody so and actually there is really no hard-and-fast definition that really holds up for any of these things so what you end up talking about is liquid properties and solid properties so it has liquid properties if it flows and quite a lot of things that seem like solids like the tar on the roads or the roads they are actually they have liquid properties because they flow and you can see that in the summer and-and-and-and the basically the the the crust of the earth that we're standing on now what you know is flowing it's flowing very aimed perceptibly to us in our in our time frame but it's flowing and that's why the continents drift apart and I crushed together and that's where the earthquakes come and that's where the volcanoes come from and so if you want you know what we are living on a planet that is has mostly liquid like properties over geological time frames and so the idea this is the third Rock from the Sun is not actually accurate at all so the liquid nests of things especially the earth crust and the prytt stick and and the roads that has this anarchic quality often that kind of gets us into trouble and it has dynamicism and whereas the solid stuff and you put it there it stays there and that's it so I guess I'm hoping anyway I hope that's kind of it's it's it's hard to tell basically one of the things talked about is that rocket fuel and then you've talked about our earth and the structure fire earth and about how important liquids are to us on earth now there's a lot of talk about going out to other planets and what we might find there and there's one particular liquid that they're really hoping they're going to find can you tell us a bit about why it is that this liquid is so important yeah so when people look for life and other planets and in other star systems they they're often looking for a planet that orbits the Sun that has a particular temperature range that they think it will be in and the reason for that is because they because essentially we believe that water is particularly unique perhaps uniquely suited towards the spontaneous production of life so the current theory for life on Earth is not that it sort of emerged from the rocks or where it merged in the clouds that it emerged from probably somewhere near the hot vents at the bottom of the sea where there's a unique combination of chemistry that allows molecules to intertube ounce against each other and in many different combinations so we're talking about a lifeless planets from the from the beginning right and you've got these molecules but then - and that bouncing together a meeting is happens a lot in liquids because liquids are constantly moving around that's what liquids do in solids things do move around but they move around really slowly and then gases if they do bump together right and there's a lot of combination going on but the energy is so high that if something magic happened you got a molecule that sort of does something special it almost immediately breaks up in and and flies around so liquid seems to be this spot this this kind of this state of matter where you can get a lot of recombination or trying out if you like the universe trying out lots of combinations of molecules and then if one of them happens to catalyze ie that means it kind of makes possible another molecule that's exactly the same you get this sort of self catalytic things you can get a building of a structure a sort of so-called self-organization and that's what happens inside ourselves right our cells build proteins like that so we are this you know this we self organize and we believe that well we see this in the experiments and I say we this is the scientific body of many many people doing experiments that that you know lots of different liquids allow this property to happen so that's one thing that's special about water and liquids in general so why water well water is the so-called universal solvent and that's all the same with the with the alcohol question is that water will dissolve organic molecules so-called carbon-based molecules if they have little little groups like like the the Oh H group that's that allows them to dissolve in water because they they become charged and water has this amazing ability to both dissolve organic molecules and things like sodium and you know the you know other stuff ionic stuff and so it's this melting pot of carbon chemistry let's say and some and some other stuff and you say well why does that matter well the funny thing is when you look at the periodic table and you go what molecules can you build from hydrogen is this many and what Mel's can you build from helium anyway any Gura any what my other skills can you bill from heart from carbon and it goes into the gazillion like for some reason the size of the carbon atom and it's the fact it's got four bonds just has an explosion of chemistry possibilities which is unlike any other element in the periodic table so there's something special so when people think oh there might be life silicon life somewhere in the universe they're kind of making they're saying silicon has that similar ability but it doesn't really carbon is this unique it seems to be unique atomic potential so you add this carbon potential with this liquid state where they're banging together each other and and that's where we believe us all of us this primeval soup arrived from so when you look for it in other planets because we're looking for liquid water because we believe that carbon molecules are pretty plentiful we're not plentiful in in real terms but they're around and we've seen them in space and we think that they're around and there's amino acid type things that naturally occur so if you find water and they're around then maybe there's life that's why we look there why can you not flush some organic chemicals such as cyclohexane down the sink when you say why and you can obviously but you shouldn't is that you say well I guess we were poisoning you're poisoning the the the ecosystems on um you know there's a quite a few I mean I think we've become more aware of the fact that it used to be when I was in the lab that you basically just could dilute something enough it was fine to go on the sink seem to remember that was the general rule what's this I don't know turn the tap on it'll be fine and occasionally some someone with Cameron sheet and knock on the door ago did anyone you know there'd be this enormous slick so we just become I think the truth is that we probably never should have done it before with most most of the stuff we make has an effect on the organisms of the planet and we're upsetting some equilibrium somewhere aren't we and and we're we're trading off the upsetting of a natural ecosystem equilibrium which was around before we arrived here and you know we've upset it quite a lot anyway just being us and and the economic utility or in this case in a lab situation whether you're going to discover something that's important for Humanity and I suppose you're always trading off the risk right and there and the benefit and I suppose we've become more and more cautious about is that really you know have are we just being you know are we just throwing you know what the risk is is becoming too high I think for us and that we should just be more careful and I think I think I welcome that basically because I you know we you look at the kind of if you think that water poisoning of whole populations is a thing of the past and clearly did used to happen a lot you're wrong like there's still today in America there's been a case in Detroit of lead poisoning wholesale lead poisoning of the whole population of Detroit because of basically not paying attention to what you know what is getting the up in the drinking water and so you know I think we just we need to get to a level of kind of consciousness about the fact that when we put something down the sink it's part of our environment I think that's why a couple of questions so there's there's one over here just towards the back thanks it's great you were talking about alternative fuels for planes and I was wondering this why doesn't hydrogen because people talk about hydrogen sells for cars and everything shouldn't it work for planes as well because pre-light yeah and it did used to so the first form of commercial flight was hydrogen Zeppelin's and airships and they competed and were the dominant form of crossing the Atlantic bye bye bye bye air in the early 20th century and amid 20 almost the mid 20th century and they got in the end out competed by that by the internal combustion engine but the thing was and this is pertinent to the point was that when the engine itself and the fuel system and everything around it is heavy which it almost always is you need to be very efficient in the way you use that fuel in order to be able to take off you know to to compensate for that weight in the case of hydrogen as a fuel rather than as a buoyancy measure which is what the airships were using it as you've got a hat you because it's a gas you need a lot of equipment to keep it compressed and that's heavy and we don't and and it's usually steel and to make it safe it's very thick and so it seems very like it seems almost like flight is the last place in which that work that that equation of energy density to weight will ever work if you ask me and I think people are fine to talk come around to this is that although electric cars seem to be the future everyone's sort of agreed that lithium batteries however limited they are they are they are they're 300 miles is gonna be enough mostly for people and that's going to be fine it's the infrastructure we need to get sorted but for shipping moving away from diesel for shipping and diesel is the absolute fuel of choice for almost all the ships and 90% of all the goods in the world is diesel ships so it's a big sector to move away that is probably going to be hydrogen because you don't need to worry about the way in the ocean and also for hydrogen to be safe you need it to be an infrastructure that's very well secured and ships always come into port so they come into port they pick up their hydrogen they go back out again so feels like shipping moving to hydrogen is the most likely cars to batteries planes I can't believe it we won't stick with liquid fuels I can't believe it it's just the energy density ratio is but that's a guess so I think there's just I make sure I've got it's someone over here just right right in the middle if you can pass the microphone down and then I'll come to it someone over there next why is nitroglycerin so reactive yeah so the it's obviously a molecule that is stable because it is a molecule and you can have it and there it is but but it has if you rearrange the atoms that makes it make make part of it either nitrogen the oxygen the carbon hydrogen you can make nitrogen gas and carbon dioxide and water out of it and the question is which one is more stable and if it's if they're close to being the same sort of stability then the one state can easily go into the other state like there's not much stopping it and with anyway so well surely they can go back again but that's the thing that doesn't happen because once one of these tips over into creating co2 it's a gas and it fills a large volume and it knocks the next one into tipping over and that fills a large volume so you get what's called a chain reaction so that the the crucial thing is that it's that once it goes the whole thing goes and that's what that's the hallmark of an explosive as opposed to a combustible material like kerosene I you just not mentioned you define liquid as something with a flowing property so I'm just wondering what's flowing liquid crystal display yeah yeah I mean so is it is a liquid crystal which is the screen on lots of your phones in there if you have them and and and lots of TVs so it's one of the dominant forms of display technology and what's the original you know digital watch and still is in my case technology what's liquid in there and yeah so I mean those will flow I mean those those they are sheets of a molecule of molecules thick of a liquid so in that sense they're probably not gonna flow in your watch or in your screen but though if you take those in bulks they Flo and and yet in certain temperature ranges they will organize into an organic regular array which is their crystalline quality the people who first invented liquid crystals were very uncomfortable with this word liquid crystal because it seems confusing because yeah they're not really crystals it in the same way I mean they they they have they have order but they're not crystals and so the liquids are you know changing neighbors and that sort of thing but and that that's a hallmark of liquids - that they changed neighbors quite often but you're right there's it's a it's a gradient and you know that's another thing that's confusing and and sort of yeah thank you everyone for a fantastic evening and I see such brilliant questions and [Music] you

Channel: The Royal Institution

Views: 14,186

Keywords: Ri, Royal Institution, mark miodownik, liquid soap, science, physics, chemistry

Id: qP6dgBD2LI8

Length: 31min 52sec (1912 seconds)

Published: Wed Jul 17 2019