5 ms·
Helium is very hard to store since it's a noble gas and so monatomic; I think it's smaller even than H2. So storing it (and H2 for that matter) is hard. Stran
by pmayrgundter 4y ago
Helium is very hard to store since it's a noble gas and so monatomic; I think it's smaller even than H2. So storing it (and H2 for that matter) is hard.
Strangely, their material is able to do that while also passing water, H20, which is a much larger molecule. They suggest in the summary that there's more going on than just the size of the porosity. Haven' read more.
Maybe someone else will know how useful this is for He or H2 in solution.. I'd imagine they'd vaporize out.
Might also be useful for drying H2 after electrolysis
- mensetmanusman 4y agoThe kinetic diameter of water is smaller than helium because its polar nature allows it to adsorb and diffuse across solid surfaces. This behavior helps it fit through small holes better than helium can.
- jhoechtl 4y agoThat sounds counterintuitive. I have a leak-free water supply yet bet it wouldn't be Helium thight.
- tbrownaw 4y agoThere's a fun experiment where you can grease a kitchen strainer and if the holes are small enough it'll hold water because of the surface tension.
- twawaaay 4y agoAnd at the same time it will pass a thick oil... all due to surface tension, polarity, etc. Which is to say don't think about the filter as a geometrical sieve that has holes that pass molecules solely based on their size (either it fits or not). This is not true even at macro level.
- whatshisface 4y agoYour plumbing is leak-tight, but it's not water vapor-tight.
- fsckboy 4y agoplumbing is not water vapor tight?
- blatant303 4y agoPlumbing for gaz and water follow different norms and pursue different sealing strategy. This distinction is omnipresent in gasket and screw thread engineering.
- hgomersall 4y agoAt the molecular level, nobody cares about your intuition.
- julienfr112 4y agoso true
- rkagerer 4y agoWhat is kinetic diameter?
- mensetmanusman 4y agohttps://pubs.acs.org/doi/10.1021/jp412588f https://pubs.acs.org/doi/10.1021/jp412588f Has to do with how to define the diameter of a molecule/atom when you consider how it interacts with other matter. Atoms are fuzzy since they are mostly electrons moving about, thus there are a few different ways to define diameter depending on how this cloud behaves.