The concept of solid liquid gas only really applies to pure uniform molecules packed next to each other.
If you spray water steam onto a ski slope you get snow, which compacts and sags.
Sure, the ice crystal is solid, but the entire structure is fluid, and can flow like avalanches and glaciers.
[quote=“TheBori, post:11, topic:512181”]
No, sorry; I’m a mechanical engineer, University of Illinois. But I took a class in CE because I found it a fascinating area of study.
I recall that the definition I was given in school was that a solid had it’s particles held in place (albeit vibrating) and a liquid had them slide over each other (while they had sufficient energy to float freely in a gas).
From this, it could be said that the difference is fairly analogue (since it’s a matter of how much a solid can move before you decide that it’s a liquid).
A stress ball is an easilly deformable polymer foam. As such the polymer is a solid. However, the individual chains in the polymer are free to move locally, but held in rough place by crosslinks. So on a local molecular level it looks like a liquid, on a larger scale a solid. Without the crosslinks it would be free to flow (slowly) like a thick liquid or putty.