Science! By Ryan Whitwam Jun. 6, 2014 2:31 pm
As far as we know, life is completely dependent on water. This particular arrangement of oxygen and hydrogen has unique properties as a solvent, a chemical reactant, and more. That also leads to some very interesting behavior that seems, at times, completely counterintuitive. It’s such a remarkable substance that we can be wowed by just a few seconds of video, perfect for GIFs. Check out the gallery above for each GIF, then read the descriptions below to learn what’s going on in each one.
[h=3]1. Marangoni effect[/h]Water has a great deal of natural surface tension due to the polarity of individual molecules. Each one has a partially positive and partially negative end, resulting in intermolecular hydrogen bonds that make water stick together, so to speak. Soap decreases the overall surface tension of water while also stabilizing it via the Marangoni effect. As the soap film stretches, the surface concentration of soap decreases and water fills in the gaps to increase surface tension locally. Soap essentially strengthens the weakest parts of the bubble. So, what’s happening in this GIF is the Marangoni effect healing disruptions in the surface of the bubble, preventing it from popping.
[h=3]2. Water bridge[/h]As pointed out above, water is a very polar molecule, which results in its high surface tension. In this GIF, a bridge of water is stretched way beyond what you’d think possible. This is happening because there is a high voltage current running through the water, which stabilizes the water’s surface tension.
[h=3]3. Water flowing uphill[/h]Water does a lot of odd stuff, but flowing uphill isn’t usually one of them. What you’re seeing here is an example of the Leidenfrost effect. When a liquid comes in contact with a surface that is considerably hotter than its boiling point, a cushion of vapor forms under the droplet. This keeps it from boiling off too fast and allows it to be pushed slightly uphill by the vapor.
[h=3]4. Bending a stream of water[/h]Water is a polar molecule, so the positive and negative ends make like a tiny magnet. This GIF depicts a neat demonstration of that fact that you can do at home. Rubbing the rod causes a buildup of negative charge, and that affects the water molecules in the stream, bending it closer.
[h=3]5. Aerogel water[/h]
This might not look like water, but it is mostly. These water droplets have been dyed with food coloring and coated in aerogel powder. This *material has extremely low density and thermal conductivity, but is still incredibly strong. The coating of aerogel sticks to the surface of the droplet and essentially makes it hydrophobic. Yes, hydrophobic water (sort of).
[h=5]6. Alka Seltzer in space[/h]It’s that surface tension thing again. Even in space, water tends to clump together because of its high polarity. In this GIF, an Alka Seltzer tablet is dropped into a floating bubble of water. That’s really all there is to it. It just looks awesome. Kind of oddly satisfying.
[h=3]7. Super-hydrophobic knife cuts water[/h]This GIF shows a blade created by researchers at Arizona State University slicing a water droplet in half. It can do this because the zinc-copper alloy has been chemically treated in such a way that it is incredibly hydrophobic — that is, it repels water. It could be of use in biomedical science as a way to separate liquids without all that troublesome splashing.
[h=3]8. Supercooled water[/h]Water normally freezes at its freezing point, which makes sense. However, if you cool it gradually in a very smooth container with no disruptions that might act as a nucleation site for ice crystals, it’s possible to keep it liquid below freezing. Give that container a little smack, and the disturbance can cause spontaneous crystallization of the water molecules. That’s what you see going on in the GIF.
[h=3]9. Cutting an apple with water[/h]Despite being a liquid at room temperature, water can be pretty solid in the right circumstances. Many liquids are incompressible, meaning applying pressure to them won’t decrease the volume (it doesn’t become more dense). That’s why the pressure at the bottom of the ocean is so crushing. It’s the same if you spray water out of a narrow opening. The force increases as pressure on the fluid does, so it can slice an apple right in half.
[h=3]10. Hydrogel beads[/h]No, this isn’t some kind of space-age material straight out of NASA. Hydrogel beads can be obtained at your local craft shop. They are commonly used to store water in flower arrangements and to absorb moisture in sweatbands. These are somewhat large ones, and the water has been dyed with food coloring, but those beads really swell up. They’re made of polymers that can absorb about 30 grams of water for every one gram of polymer. They also look strangely tasty. I want to bite them.
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As far as we know, life is completely dependent on water. This particular arrangement of oxygen and hydrogen has unique properties as a solvent, a chemical reactant, and more. That also leads to some very interesting behavior that seems, at times, completely counterintuitive. It’s such a remarkable substance that we can be wowed by just a few seconds of video, perfect for GIFs. Check out the gallery above for each GIF, then read the descriptions below to learn what’s going on in each one.[h=3]1. Marangoni effect[/h]Water has a great deal of natural surface tension due to the polarity of individual molecules. Each one has a partially positive and partially negative end, resulting in intermolecular hydrogen bonds that make water stick together, so to speak. Soap decreases the overall surface tension of water while also stabilizing it via the Marangoni effect. As the soap film stretches, the surface concentration of soap decreases and water fills in the gaps to increase surface tension locally. Soap essentially strengthens the weakest parts of the bubble. So, what’s happening in this GIF is the Marangoni effect healing disruptions in the surface of the bubble, preventing it from popping.
[h=3]2. Water bridge[/h]As pointed out above, water is a very polar molecule, which results in its high surface tension. In this GIF, a bridge of water is stretched way beyond what you’d think possible. This is happening because there is a high voltage current running through the water, which stabilizes the water’s surface tension.
[h=3]3. Water flowing uphill[/h]Water does a lot of odd stuff, but flowing uphill isn’t usually one of them. What you’re seeing here is an example of the Leidenfrost effect. When a liquid comes in contact with a surface that is considerably hotter than its boiling point, a cushion of vapor forms under the droplet. This keeps it from boiling off too fast and allows it to be pushed slightly uphill by the vapor.
[h=3]4. Bending a stream of water[/h]Water is a polar molecule, so the positive and negative ends make like a tiny magnet. This GIF depicts a neat demonstration of that fact that you can do at home. Rubbing the rod causes a buildup of negative charge, and that affects the water molecules in the stream, bending it closer.
[h=3]5. Aerogel water[/h]
This might not look like water, but it is mostly. These water droplets have been dyed with food coloring and coated in aerogel powder. This *material has extremely low density and thermal conductivity, but is still incredibly strong. The coating of aerogel sticks to the surface of the droplet and essentially makes it hydrophobic. Yes, hydrophobic water (sort of).
[h=5]6. Alka Seltzer in space[/h]It’s that surface tension thing again. Even in space, water tends to clump together because of its high polarity. In this GIF, an Alka Seltzer tablet is dropped into a floating bubble of water. That’s really all there is to it. It just looks awesome. Kind of oddly satisfying.
[h=3]7. Super-hydrophobic knife cuts water[/h]This GIF shows a blade created by researchers at Arizona State University slicing a water droplet in half. It can do this because the zinc-copper alloy has been chemically treated in such a way that it is incredibly hydrophobic — that is, it repels water. It could be of use in biomedical science as a way to separate liquids without all that troublesome splashing.
[h=3]8. Supercooled water[/h]Water normally freezes at its freezing point, which makes sense. However, if you cool it gradually in a very smooth container with no disruptions that might act as a nucleation site for ice crystals, it’s possible to keep it liquid below freezing. Give that container a little smack, and the disturbance can cause spontaneous crystallization of the water molecules. That’s what you see going on in the GIF.
[h=3]9. Cutting an apple with water[/h]Despite being a liquid at room temperature, water can be pretty solid in the right circumstances. Many liquids are incompressible, meaning applying pressure to them won’t decrease the volume (it doesn’t become more dense). That’s why the pressure at the bottom of the ocean is so crushing. It’s the same if you spray water out of a narrow opening. The force increases as pressure on the fluid does, so it can slice an apple right in half.
[h=3]10. Hydrogel beads[/h]No, this isn’t some kind of space-age material straight out of NASA. Hydrogel beads can be obtained at your local craft shop. They are commonly used to store water in flower arrangements and to absorb moisture in sweatbands. These are somewhat large ones, and the water has been dyed with food coloring, but those beads really swell up. They’re made of polymers that can absorb about 30 grams of water for every one gram of polymer. They also look strangely tasty. I want to bite them.
- [h=4]1. Marangoni effect[/h]Soap stabilizing a bubble.
- [h=4]2. Water bridge[/h]Not your average surface tension.
- [h=4]3. Water flowing uphill[/h]It’s hot, hot, hot!
- [h=4]4. Bending a stream of water[/h]Careful with that science pole.
- [h=4]5. Aerogel water[/h]They won’t pop.
- [h=4]6. Alka Seltzer in space[/h]So satisfying.
- [h=4]7. Super-hydrophobic knife cuts water[/h]You call that a knife?
- [h=4]8. Supercooled water[/h]Left it in the freezer too long.
- [h=4]9. Cutting an apple with water[/h]Who needs lasers?
- [h=4]10. Hydrogel beads[/h]They look tasty.
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