Liquid lighter than air?

#1
This is definitely not for a setting I plan to use if I can get the science down. Definitely not that. 

So anyway, I've been doing a tiny bit of research and just want some people's ideas about what if a liquid was lighter than air. Of course one idea being that the liquid would float to the top of air until stopped by a solid or something that is heavier than it. However, a gases property will change over time depending on the temperature. So for instance if a liquid is lighter than the gas one moment, it'll float up, but as the day goes on the gas may become heavier than the liquid, pushing it down to the ground. 

That's the most basic research I've done right now and would like to know if someone else has anymore insight into how this would work.

Re: Liquid lighter than air?

#4
Probably not, at least not if both are under the same conditions. The density of liquids is pretty constant, while gases can become denser under enough pressure. So you could in theory get a gas that is heavier than the lightest liquids, but under such conditions the liquids would've likely become compressed into ice and be heavier than the gas anyway. Maybe if you add enough ani-freeze? :D 

Re: Liquid lighter than air?

#6
For liquid to be denser than air, you'd have to compress the air to increase its density. That's a lot of pressure that everything would be under, and yeah, the water would freeze. I suppose there's potential for a frozen wasteland setting for any story that you'd want to write that into Of course, normal humans would be entirely unable to survive in such an environment. Not because of the lack of water, but because of the ridiculous pressure.

Re: Liquid lighter than air?

#7
Right, so while the density and temperature of the atmosphere varies as you rises (though generally, both decrease), as the liquid floats upwards, it would only cool down, it would not change in density.  Conceivably, there may be some boundary layer in the atmosphere where the liquid is less dense than below atmosphere but more dense than the atmosphere above.  In that instance, depending on total volume, you could have rivers or lakes or this liquid in the sky. One other issue is that as the pressure drops, then potentially the boiling point for the liquid falls. Depending on how that happens, it could boil mid-atmosphere and then disperse.

You should also look into helium and how to reacts in Earth's atmosphere.  Basically, any helium floats up to the very edge of space and then gets stripped away from the Earth.  

Re: Liquid lighter than air?

#8

luda305 Wrote: You should also look into helium and how to reacts in Earth's atmosphere.  Basically, any helium floats up to the very edge of space and then gets stripped away from the Earth.
Huh.


Considering helium is one of the few truly non-renewable resources on earth and we keep pumping it into balloons, it seems quite amazing there's still any left. 

Re: Liquid lighter than air?

#10
You could look into the Leidenfrost effect. It's not strictly a liquid being less dense than air but it is pretty cool to see.

Unfortunately, under standard Earth conditions, it's not possible for liquids to be less dense than even the densest gases known to us. I couldn't quote them off the top of my head but they're probably easy enough to google relative densities of these. I couldn't comment on the atmosphere's of other planets though - but the pressures needed for this scenario would probably make it difficult for anything other than unicellular extremophiles to survive. If they're able to live there at all.

https://www.youtube.com/watch?v=gjsMV1MglA4

Re: Liquid lighter than air?

#12

LambentTyto Wrote:
Gryphon10 Wrote: That's the most basic research I've done right now and would like to know if someone else has anymore insight into how this would work.
No clue. You writing hard sci fi?
No its soft sci-fi, but also high fantasy so I can work around some aspects but I also want to know certain aspects about things that I'm writing about. For instance if I can get an idea about whats holding back something from happening in real life, like water being lighter than air, then I can come up with a system that can work around that. Or maybe there is a way to make it work and I can just implement that into my story, since I got an arc in mind(two actually) that revolves around a setting that involves liquids doing things that is normally impossible. I fall under the umbrella that says do at least basic research around what you're writing. 

Re: Liquid lighter than air?

#13
Well, regardless of its form if it's less dense than air it should float up.

Just make it that said liquid forms microscopic bubbles that inside that are devoid of air. Or that those almost invisible bubbles are filled with some special anti gravity gas. Or just normal gas.

In my opinion, if it's a fantasy setting, just make it float and give some random excuse that fits the setting... or none at all. Depends.

Re: Liquid lighter than air?

#14

Gryphon10 Wrote:
LambentTyto Wrote:
Gryphon10 Wrote: That's the most basic research I've done right now and would like to know if someone else has anymore insight into how this would work.
No clue. You writing hard sci fi?
No its soft sci-fi, but also high fantasy so I can work around some aspects but I also want to know certain aspects about things that I'm writing about. For instance if I can get an idea about whats holding back something from happening in real life, like water being lighter than air, then I can come up with a system that can work around that. Or maybe there is a way to make it work and I can just implement that into my story, since I got an arc in mind(two actually) that revolves around a setting that involves liquids doing things that is normally impossible. I fall under the umbrella that says do at least basic research around what you're writing.
In that case, I would switch concepts around somehow. For example, you could just do away with the concepts of clouds, and replace them with liquid. Or switch the physics of water with the physics of gas, and end up with a planet with no water on the ground but instead encasing the planet. Or reverse the evaporation/rain cycle and have water rise as liquid and descend as vapor for some reason. 


So there'd be some science in there and you can use existing concepts of it, but it would be a "what if this was totally different" rather than being accurate. 

Re: Liquid lighter than air?

#16

Haust Wrote:
Fastus Wrote: Just make it that said liquid forms microscopic bubbles that inside that are devoid of air. Or that those almost invisible bubbles are filled with some special anti gravity gas. Or just normal gas.
That's just perfectly common vapor, though.


Which planet vapor? If you mean water vapor found on earth I think you might have mistaken something.

Re: Liquid lighter than air?

#17

Fastus Wrote:
Haust Wrote:
Fastus Wrote: Just make it that said liquid forms microscopic bubbles that inside that are devoid of air. Or that those almost invisible bubbles are filled with some special anti gravity gas. Or just normal gas.
That's just perfectly common vapor, though.


Which planet vapor? If you mean water vapor found on earth I think you might have mistaken something.
Microscopic bubbles would just act as vapor. It's mist at that point. 

Re: Liquid lighter than air?

#19

The Wrote: reminds me of liquid glowstone in minecraft :)

If the liquid had some sort of antigravity property, possibly when charged with magic?

If you go science, it's tough to come up with anything.
Charged with magic sounds fun. Maybe everything that has enough electrical conductivity could get charged with magic instead and start floating? Metal would start floating away too, but.. 

Re: Liquid lighter than air?

#20

Haust Wrote:
Fastus Wrote:
Haust Wrote:
Fastus Wrote: Just make it that said liquid forms microscopic bubbles that inside that are devoid of air. Or that those almost invisible bubbles are filled with some special anti gravity gas. Or just normal gas.
That's just perfectly common vapor, though.


Which planet vapor? If you mean water vapor found on earth I think you might have mistaken something.
Microscopic bubbles would just act as vapor. It's mist at that point.


No.

Imagine water, but with countless little bubbles inside. They are formed by the liquid and can't break free of it. So minuscule that they're hard to see, all kept at the same distance.

If those bubbles were empty, or filled with a gas much lighter than air, with enough of them inside the liquid, they would lower the fluid density enough that it would be lower than the air's. Thus floating liquid.