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cracksmack85 t1_jd4k75m wrote

Reply to comment by westernguy339 in Can a single atom be determined to be in any particular phase of matter? by Zalack

Semi-related question - when I took gen chem in college, if a solid was dissolved in a liquid it was always denoted as “aqueous” and we were told to treat it as a liquid, but it was never really clear to me whether that substance is a liquid or a solid. Can you explain the “aqueous” designation?

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[deleted] t1_jd4mf0y wrote

Aqueous here means that the solution which constitutes a solvent and solute, has water as the chosen solvent.

Example being Sodium Chloride. Sodium Chloride (aq) simply means that you have a saline solution. The individual atoms of Sodium Chloride are dissolved in liquid water.

I wouldn't really call NaCl a liquid if you have NaCl (aq) because you're no longer dealing with pure NaCl. The aqueous solution is a liquid though.

This leads to an interesting question about solids that do not dissolve in a liquid. Here you're dealing with a type of colloid (effectively one phase suspended in another phase) And the dispersed compound does not have to be solid btw- it can be liquid (such as milk).

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cdcformatc t1_jd5d0dx wrote

Liquid salt to me makes me think of molten salt heated past it's melting temperature, which is very different than an aqueous solution.

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Angdrambor t1_jd7y889 wrote

It gets even more fun when you look at materials like Ice or Steel, which have like a dozen solid phases each.

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octonus t1_jd54mix wrote

We discuss states of matter in terms of how a molecule interacts with its neighbors. If the solvent is a liquid (water in the case of aqueous solution), all interactions that you would care about are liquid like. In the case of a solid solution ie. bronze they would be solid-like.

The key reason we note it as being a solution rather than a liquid is to point out that the neighbors a molecule interacts with are the solvent, rather than molecules of the same type.

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RestlessARBIT3R t1_jd4n0l2 wrote

Aqueous just means that it’s dissolved in a liquid. Ionic things dissolved in a liquid get covered in water molecules because the water molecules are polar and the ions are charged. Non-ionic things dissolved in liquid are usually just polar and can form hydrogen bonds with the water molecules so that it looks like a single solution as opposed to when things don’t dissolve

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