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  • Thank you.

  • Water is quite beautiful to look at,

  • and I guess you probably all know that you're two-thirds water --

  • you do, don't you? Right.

  • But you may not know that because the water molecule is so small,

  • that two-thirds translates into 99% of your molecules.

  • Think of it, 99% percent of your molecules are water.

  • So, your shoes are carrying around a blob of water essentially.

  • Now, the question is, in your cells,

  • do those water molecules actually do something?

  • Are these molecules essentially jobless

  • or do they do something that might be really, really interesting?

  • For that matter are we even really sure that water is H₂O?

  • We read about that in the textbook,

  • but is it possible that some water is actually not H₂O?

  • So, these are questions whose answers are actually not as simple

  • as you think they might be.

  • In fact, we're really in the dark about water, we know so little.

  • And why do we know so little?

  • Well, you probably think that water is so pervasive,

  • and it's such a simple molecule,

  • that everything ought to be known about water, right?

  • I mean you'd think it's all there.

  • Well, scientists think the same.

  • Many scientists think, och, water it's so simple,

  • that everything must be known.

  • And, in fact, that's not at all the case.

  • So, let me show you, to start with, a few examples of things about water

  • that we ought to know, but we really haven't a clue.

  • Here's something that you see every day.

  • You see a cloud in the sky and, probably, you haven't asked the question:

  • How does the water get there?

  • Why, I mean, there's only one cloud sitting there,

  • and the water is evaporating everywhere,

  • why does it go to this cloud forming what you see there?

  • So, another question: Could you imagine droplets floating on water?

  • We expect droplets to coalesce instantly with the water.

  • The droplets persist for a long time.

  • And here's another example of walking on water.

  • This is a lizard from Central America.

  • And because it walks on water it's called the Jesus Christ lizard.

  • At first you'll say, "Well, I know the answer to this,

  • the surface tension is high in water."

  • But the common idea of surface tension

  • is that there's a single molecular layer of water at the top,

  • and this single molecular layer is sufficient to create enough tension

  • to hold whatever you put there.

  • I think this is an example that doesn't fit that.

  • And here's another example.

  • Two beakers of water. You put two electrodes in,

  • and you put high voltage between them and then what happens is a bridge forms,

  • and this bridge is made of water, a bridge of water.

  • And this bridge can be sustained

  • as you move one beaker away from the other beaker,

  • as much as 4 centimeters,

  • sustained essentially indefinitely.

  • How come we don't understand this?

  • So, what I mean is that there are lots of things about water

  • that we should understand, but we don't understand,

  • we really don't know.

  • So, okay, so what do we know about water?

  • Well, you've learned that the water molecule

  • contains an oxygen and two hydrogens.

  • That you learn in the textbooks. We know that.

  • We also know there are many water molecules,

  • and these water molecules are actually moving around microscopically.

  • So, we know that. What don't we know about water?

  • Well, we don't know anything about the social behavior of water.

  • What do I mean by social? Well, say, sitting at the bar

  • and chatting with your neighbor.

  • We don't know how water molecules actually share information or interact,

  • and also we don't know about the actual movements of water molecules.

  • How water molecules interact with one another,

  • and also how water molecules interact with other molecules

  • like that purple one sitting there. Unknown.

  • Also the phases of water.

  • We've all learned that there's a solid phase,

  • a liquid phase and a vapor phase.

  • However, a hundred years ago,

  • there was some idea that there might be a fourth phase,

  • somewhere in between a solid and a liquid.

  • Sir William Hardy, a famous physical chemist,

  • a hundred years ago exactly,

  • professed that there was actually a fourth phase of water,

  • and this water was kind of more ordered than other kinds of water,

  • and in fact had a gel-like consistency.

  • So, the question arose to us --

  • you know, all of this was forgotten, because people began, as methods improved,

  • to begin to study molecules instead of ensembles of molecules,

  • and people forgot about the collectivity of water molecules

  • and began looking, the same as in biology,

  • began looking at individual molecules and lost sight of the collection.

  • So, we thought we're going to look at this

  • because we had some idea that it's possible

  • that this missing link, this fourth phase,

  • might actually be the missing link

  • so that we can understand the phenomena regarding water that we don't understand.

  • So, we started by looking somewhere between a solid and a liquid.

  • And the first experiments that we did get us going.

  • We took a gel, that's the solid, and we put it next to water.

  • And we added some particles to the water

  • because we had the sense that particles would show us something.

  • And you can see what happened

  • is that the particles began moving away from the interface

  • between the gel and the water,

  • and they just kept moving and moving and moving.

  • And they wound up stopping at a distance

  • that's roughly the size of one of your hairs.

  • Now, that may seem small, but by molecular dimensions

  • that's practically infinite. It's a huge dimension.

  • So, we began studying the properties of this zone,

  • and we called it, for obvious reasons, the exclusion zone,

  • because practically everything you put there would get excluded,

  • would get expelled from the zone as it builds up,

  • or instead of exclusion zone, EZ for short.

  • And so we found that the kinds of materials

  • that would create or nucleate this kind of zone,

  • not just gels, but we found that practically every water-loving,

  • or so-called hydrophilic surface could do exactly that,

  • creating the EZ water.

  • And as the EZ water builds, it would expel all the solutes

  • or particles, whatever into the bulk water.

  • We began learning about properties, and we've spent now quite a few years

  • looking at the properties.

  • And it looks something like this:

  • You have a material next to water and these sheets of EZ layers begin to build,

  • and they build and build and they just keep building up one by one.

  • So, if you look at the structure of each one of these planes,

  • you can see that it's a honeycomb, hexagonal kind of structure,

  • a bit like ice, but not ice.

  • And, if you look at it carefully, you can see the molecular structures.

  • So, of course, it consists of hydrogen and oxygen,

  • because it's built from water.

  • But, actually, they're not water molecules.

  • If you start counting the number of hydrogens

  • and the number of oxygens,

  • it turns out that it's not H₂O.

  • It's actually H₃O₂.

  • So, it is possible that there's water that's not H₂O, a phase of water.

  • So, we began looking, of course, more into these extremely interesting properties.

  • And what we found is, if we stuck electrodes into the EZ water,

  • because we thought there might be some electrical potential,

  • it turned out that there's lots of negative charge in that zone.

  • And we used some dyes to seek positive charge,

  • and we found that in the bulk water zone there was an equal amount of positivity.

  • So, what's going on?

  • It looked like, that next to these interfaces

  • the water molecule was somehow splitting up

  • into a negative part and a positive part.

  • And the negative part sat right next to the water-loving material.

  • Positive charges went out beyond that.

  • We found it's the same, you didn't need a straight interface,

  • you could also have a sphere.

  • So, you put a sphere in the water, and any sphere that's suspended in the water

  • develops one of these exclusion zones, EZ's, around it, with the negative charge,

  • beyond that is all the positive charge. Charge separation.

  • It didn't have to be only a material sphere, in fact,

  • you could put a droplet in there, a water droplet,

  • or, in fact, even a bubble, you'd get the same result.

  • Surrounding each one of these entities is a negative charge

  • and the separated positive charge.

  • So, here's a question for you.

  • If you take two of these negatively charged entities,

  • and you drop them in a beaker of water near each other,

  • what happens to the distance between them?

  • I bet that 95% of you would say:

  • Well, that's easy, I learned in physics, negative and negative repel each other,

  • so, therefore they're going to go apart from one another, right?

  • That what you'd guess?

  • Well, the actual result if you think about it,

  • is that it's not only the negative charge but you also have positive charge.

  • And the positive charge is especially concentrated

  • in between those two spheres,

  • because they come from contributions from both of those spheres.

  • So, there are a lot of them there.

  • When you have positive in between two negatives

  • what happens is that you get an attractive force.

  • And so you expect these two spheres to actually come together

  • despite the fact that they have the same charge,

  • and that's exactly what happens.

  • It's been known for for many years.

  • They come together, and if you have many of them, instead of just two of them,

  • you'll get something that looks like this.

  • They'll come together and this is called a colloid crystal.

  • It's a stable structure.

  • In fact, the yogurt that you might have had this morning

  • probably consists of what you see right here.

  • So, they come together because of the opposite charge.

  • The same thing is true if you have droplets.

  • They come together because of the opposing charges.

  • So, when you think of droplets, and aerosol droplets in the air,

  • and think about the cloud,

  • it's actually the reason that these aerosol droplets come together

  • is because of this opposite charge.

  • So, the droplets from the air, similarly charged,

  • come together coalesce, giving you that cloud in the sky.

  • So the fourth phase, or EZ phase, actually explains quite a lot.

  • It explains, for example, the cloud.

  • It's the positive charge

  • that draws these negatively charged EZ shells together

  • to give you a condensed cloud that you see up in the sky.

  • In terms of the water droplets,

  • the reason that these are sustained on the surface

  • for actually sometimes as long as tens of seconds --

  • and you can see it if you're in a boat

  • and it's raining, you can sometimes see this on the surface of the lake,

  • these droplets are sustained for some time --

  • and the reason they're sustained is that each droplet contains this shell,

  • this EZ shell, and the shell has to be breached

  • in order for the water to coalesce with the water beneath.

  • Now, in terms of the Jesus Christ lizard, the reason the lizard can walk,

  • it's not because of one single molecular layer,

  • but there are many EZ layers lining the surface,

  • and these are gel-like, they're stiffer than ordinary surfaces

  • so, therefore, you can float a coin on the surface of the water,

  • you can float a paperclip,

  • although if put it beneath the surface it sinks right down to the bottom.

  • it's because of that.

  • And in terms of the water bridge,

  • If you think of it as plain old, liquid, bulk water -- hard to understand.

  • But if you think of it as EZ water and a gel-like character,

  • then you can understand how it could be sustained with almost no droop,

  • a very stiff structure.

  • Okay, so, all well and good, but why is this useful for us?

  • What can we do with it?

  • Well, we can get energy from water.

  • In fact, the energy that we can get from water is free energy.

  • It's literally free. We can take it from the environment.

  • Let me explain.

  • So, you have a situation in the diagram with negative charge and positive charge,

  • and when you have two opposing charges next to each other

  • it's like battery.

  • So, really we have a battery made of water.

  • And you can extract charge from it,

  • so that is right now.

  • Batteries run down, like your cell phone needs to be plugged in every day or two,

  • and so the question is: Well, what charges this water battery?

  • It took us a while to figure that out, what recharges the battery.

  • And one day, we're