Chemical Forums
Chemistry Forums for Students => Physical Chemistry Forum => Topic started by: Dissonance on August 01, 2015, 12:29:51 PM
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Hello everyone :)
It's my first post here so I apologise if this question has been answered before. Recently, I attended a lecture on Solubility equilibria and I'm still trying to wrap my head around the concept of gases (O2 and CO2) dissolving in water.
I understand that when salts dissolve in water, the cations and anions interact with the water molecules via ion-dipole interactions. So my question is when oxygen goes into solution, what kind of interactions does it form with water molecules?
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Do you understand the interactions when non-ionic compounds, for example sucrose, dissolve in water? The reasons are similar. Also, can you postulate a possible ionic reaction with carbon dioxide and water?
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Hi Arkcon! Thanks for your quick reply
If I recall correctly, sucrose has a few hydroxyl groups attached to it and these hydroxyl groups are able to interact with water molecules via hydrogen bonding, which explains why sucrose is soluble in water. As for oxygen molecules, they are only capable of forming induced dipole interactions (London-dispersion forces). If I were to take a guess, I would think that oxygen can interact with water via "dipole-induced dipole interactions", resulting in aqueous O2.
As for carbon dioxide, I believe it reacts with water to form carbonic acid. The carbonic acid then partially dissociates in water to form hydronium cation and bicarbonate anion.
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Good answers, although I don't believe diatomic oxygen can contribute to the hydrogen bonds.