Hunangren

Hunangren t1_jd35304 wrote

No, it can't. Phases of matter are a description of some emerging properties derived by the collective behaviour of a large ensamble of atoms (or, more in general, particles). By definition such properties have no meaning in describing a single (or a few) particles.

To familiarise with the concept of collective behaviour think about yourself: you too are a collection of cells that have some emerging properties that no one single part of yourself have. For example, you can be "hungry", "tired" or "sad"; although there is no meaning in asking if any particular cell of your body is "hungry", "tired" or "sad".

The same is true for a collection of atoms. A crystal is solid, but there is no sense in calling every single atom in the crystal solid or not. A single uranium atom in a liquid is neither liquid nor solid: it is part of a liquid.

Talking about the plasma, that's a fun topic: in a sense, there are multiple orders of state of matter, describing different type of particles describing collecting behaviours. The three "canonical" state of matter (solid, liquid and gas) describe the behaviour of ensables of atoms. You can extend the logic to subatomic particles, though, obtaining that neutral atoms are the analogue to solid while plasma is the analogue of gas; or even to macroscopic scale, obtaining that "sand" is a macroscopic state of an ensable of pebbles which has a viscosity and the ability to occupy any volume, as opposed to "crystal", which is impenetrable and rigid. I suggest you the video from PBS Space Time "How Many States Of Matter Are There?" that you can find on youtube. It's really enlighting about the matter, ;)

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