Q&A: Solidity and Fluidity
Originally published:
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Solidity and Fluidity
Question
I came across a claim in your book (2 Wagons and a Hot-Air Balloon, p. 190 or so) that it makes no sense to say that a molecule has a property like solidity, fluidity, viscosity, and so on, and that these are properties that exist only at the macro level.
I would be glad to know why the claim is incorrect that if these properties exist at the macro level, then presumably they also exist at the molecular level, even though these properties have no meaning when we are talking about such a small scale of matter.
Thank you very much.
Answer
Simply because you cannot define states of solidity or fluidity with respect to a single molecule. Solidity or fluidity reflect a relationship between molecules within a collection.