Science Buddies: "Ask an Expert"

I'm trying to find a very dense gas, and an extremely light liquid.
The object is to make a liquid that can float on gas, to make a shock absorber that works in more than just up and down. I am trying to figure out a way to make a shock absorber move to side to side. It is also possible for a solid to rest on a liquid. And a solid to rest on a gas, if a vacuum is made between the gas and solid. The substance may have to be put under pressure, but would need to act at room temperature. The denses gas I've discoverd is uranium hexafluoride. Another problem would be finding a extremely light liquid at room temp. I would expect that the liquid would need to have some extremly strong bonds, while the gas would have to be very stable (however uranium hexafluoride is not stable) A problem is preventing the gas from reacting with the liquid. Radium is another thought. Any ideas into this problem would be appreciated.

grashapa1 wrote:I'm trying to find a very dense gas, and an extremely light liquid.
The object is to make a liquid that can float on gas, to make a shock absorber that works in more than just up and down. I am trying to figure out a way to make a shock absorber move to side to side. It is also possible for a solid to rest on a liquid. And a solid to rest on a gas, if a vacuum is made between the gas and solid. The substance may have to be put under pressure, but would need to act at room temperature. The denses gas I've discoverd is uranium hexafluoride. Another problem would be finding a extremely light liquid at room temp. I would expect that the liquid would need to have some extremly strong bonds, while the gas would have to be very stable (however uranium hexafluoride is not stable) A problem is preventing the gas from reacting with the liquid. Radium is another thought. Any ideas into this problem would be appreciated.

Hi, grashapa1!

This is, indeed, a challenging problem. I have been trying to think of a way to help you all day. I've asked my associates at work for assistance, and we've come to the conclusion that to produce the conditions you describe between a gas and a liguid is difficult at best, and perhaps impossible.

One example of a liquid suspended on a gas is water vapor - which is actually water droplets suspended in air. I don't know if this helps.

Perhaps a better way to try to help is for me to ask for more details about this shock absorber you are considering. It may be that there is another way to produce what you're thinking of. Could you describe what you mean by having it move side to side? How is this different from using a conventional shock absorber and turning it on its side? (I'm asking this question for clarification purposes, not to suggest an alternate method.)

Thank you OneBriiguy,
I know waterdroplets are liquids suspended on gas, but those are in small amounts. I think it would be possible to make a liquid float on a gas if temperatures differed for each substance. (Gas of radon, and liquid nitrogen would work, even if only for a few minutes)

The shock absorber idea is not my first idea. I first came up with the idea, if it was possible for a liquid to float on a gas. I know solids can float on liquids (ice). And solids can float on gas with enough pressure. The shock absorber idea came up after thinking of uses for the "liqfloat." To clarify, if a object rested on a liquid. The object would stay positioned when the motor was moving up and down, and side to side. With normal shock absorbers, one can only prevent up and down movement from being felt.

An idea I've also thought of, is to make the liquid and gases magnetic. Except if tha gas was magnetic, it would probably not be a gas. Perhaps for the liquid, it would have to be a molecule that used strong bonds, but had an irregular shape, to prevent crystallization. And for the gas, it might be a molecule in a perfect sphere?, or a certain shape, that would make it heavy, but prevent it from joining to other molecules. So this molecule is like a giant version of a noble gas.

more clarification: with a liquid, liquids will always stay parallel to the earth because of gravity. Giving the user no swinging/lateral motion along with no vertical motion. So, i guess the word would be to prevent diagonal motion.

"The heaviest known gas is Uranium hexafluoride, UF6."(Wikipedia)

random thoughts:
1) i dont understand completly, since say radon is heavier than bromine, what isn't radon at the bottom if it is heaver, could i increase the concentration of radon to make it fill more space...
2) but along that idea, what if i had a liquid, that a gas could dissolve in, to a point of insolubility, and the system could not hold anymore gas molecules, so the solution could not fall through the other gases, except with that idea, the gases would continue to move through because of gravity
3)so, what if i had a liquid who's molecules could not pass throught the molecules of a gas, such that the two shapes could not diffuse, the liquid on the gas was prevented from flowing through

grashapa1 wrote:random thoughts:
1) i dont understand completly, since say radon is heavier than bromine, what isn't radon at the bottom if it is heaver, could i increase the concentration of radon to make it fill more space...
2) but along that idea, what if i had a liquid, that a gas could dissolve in, to a point of insolubility, and the system could not hold anymore gas molecules, so the solution could not fall through the other gases, except with that idea, the gases would continue to move through because of gravity
3)so, what if i had a liquid who's molecules could not pass throught the molecules of a gas, such that the two shapes could not diffuse, the liquid on the gas was prevented from flowing through

Hello, grashapa1!

I must admit that I am somewhat out of my area of expertise here, but let me do some thinking out loud.

I think the primary reason liquids do not float on gases is not their atomic weight. It has to do with denisty. As I'm sure you know, it takes a specific amount of heat energy to convert a liquid to a gas, and part of that energy goes into the motion of the molecules. In a gas, the molecules are significantly farther apart, meaning the denisty of the gaseous form of an element is significantly less dense than the liquid form. The act of "floating" is all about displacing a volume of matter that has equal mass - something a less dense material cannot do.

I suspect what you have posted is true - that if one could control temperature and pressure one could create a situation in which a liguid could float on a gas. The practical problem is what would happen at the contact point between the liquid and the gas. If it's even possible to maintain the pressure difference (and I don't think it is) the temperature exchange is likely to be so rapid that you would not get to observe the effect you are trying to create.

It might be interesting to do an investigation into what it would take to create the situations you describe. Actually attempting them, however, is likely to take a lot of expensive equipment and expertise.

You may find others with more knowledge of this area than I have. This is my best guess based on what I have studied and seen in practice.

Best wishes!

yah, i know its complicated
The only way i could think, which is more practical of displacing the liquid, is having a magnetic gas, which exists (even oxygen is slightly magnetic).
So a possibility is using a powerful magnet to attract the gases to the bottom of the container. Examples are like when bubbles are attracted to the bottom of a cup in sodas or just normal water. Attraction keeps the bubbles at the bottom. (Now the trick would be finding a very magnetic gas.)
Also, if a liquid has a strong surface tension, it would be less willing to break and fall through the gas. So instead of a pure liquid, the liquid might be like a goo, which say, would float on a bubble pocket. Kind of like how a parachute floats on air.

grashapa1 wrote:yah, i know its complicated
The only way i could think, which is more practical of displacing the liquid, is having a magnetic gas, which exists (even oxygen is slightly magnetic).
So a possibility is using a powerful magnet to attract the gases to the bottom of the container. Examples are like when bubbles are attracted to the bottom of a cup in sodas or just normal water. Attraction keeps the bubbles at the bottom. (Now the trick would be finding a very magnetic gas.)
Also, if a liquid has a strong surface tension, it would be less willing to break and fall through the gas. So instead of a pure liquid, the liquid might be like a goo, which say, would float on a bubble pocket. Kind of like how a parachute floats on air.

Hello, grashapa1!

I must say that I am impressed with the creative thinking you are exhibiting in your posts. You are definitely "thinking outside of the box", as they say. This bodes well for your future success. Please continue!

I send along my very best wishes for success in this and other projects.

Thank you Brian, You said that this idea was out of your expertise previously. Could you please tell me what you specialize in? Your occupation says that you are a engineering specialist, but that could occupy multiple fields. I would like to know what you specialize in, because this is not my only idea, and I feel that if I posted them, they would never be answered to. You seem like you, and maybe a few others, are the only "experts" in "ask an expert." Thank you for your remarks.

grashapa1 wrote:Thank you Brian, You said that this idea was out of your expertise previously. Could you please tell me what you specialize in? Your occupation says that you are a engineering specialist, but that could occupy multiple fields. I would like to know what you specialize in, because this is not my only idea, and I feel that if I posted them, they would never be answered to. You seem like you, and maybe a few others, are the only "experts" in "ask an expert." Thank you for your remarks.

The title I use in this forum is the best I could come up with. I am not an expert in anything, and my current job title, "Corporate Systems Engineer" does not accruately reflect my career and educational experiences. It also does not accurately reflect my love of science. I get a big kick out of doing the research and responding to the questions in this forum. I think it's fun!

I am an Electircal Engineer by training, and a Software Engineer by experience. I have also worked as a machinist, an engineering technician, and a truck driver. In my current job, I lead small teams of engineers to develop and deploy solutions for our company's customers' problems. This gives me exposure to many different aspects of technology. Mostly, though, what qualifies me to participate in this forum is that I think like an engineer. Engineer's solve problems, and participating in this forum is like one huge problem-solving exercise!

I hope this helps you.

yes, it explains everything. lol You're similar to someone i know, who's in your position.