From: someone@microsoft.com
"Krzysztof Mitko" wrote in message
news:0001HW.215FD08B0045EB93700000E8C2EF@news.neostrada.pl...
> On 29 Sep 2018, Peter Percival wrote
> (in article ):
>
>> (i) When oxygen is dissolved in water is it molecular oxygen or atomic
>> oxygen that dissolves?
>
> Molecular (O2, not O).
>> (ii) Does whatever is dissolved float around "at random" or do the
>> molecules or atoms (as the case may be) of oxygen associate themselves
>> with water molecules in some predictable way?
>
> It just floats around.
>> (iii) When a glass with dissolved oxygen (and other atmospheric gasses)
>> is placed in sunlight, oxygen (and etc) appears as bubbles on the glass.
>> What is going on here?
>
> Gas solubility decreases as water heats up, so part of gas previously
> dissolved is evolving.
>> Many thanks for any answers.
>
> --
> They laughed at Columbus, they laughed at Fulton, they laughed at the
> Wright
> Brothers. But they also laughed at Bozo the Clown.
>
Don't forget that when the gas methane is dissolved in water, it creates
ordered structure. Lower the temperature and you get methane ice, a
clathrate or cage structure. Methane hydrate looses methane at a
temperatures well above H2O freezing. It sublimes. If one were to control
pressure and temperature in the lab, one could purify methane hydrate by
flask to flask sublimation.
Does that relate to water structure when molecular O2 is dissolved in it?
Maybe. For methane, symmetry and hydrophobicity are important when dissolved
in H2O. O2 has a low order of symmetry and it is hydrophobic. O2 does not
dissolve well in H2O, perhaps due to the energy of structure making. H2O has
a bent structure with a permanent dipole moment. -OH is used hydrophilic
interactions. Hence water need to orient with -O- pointed at the O2
molecule. Water cries out, "that's more energy than I want", so O2 is
readily expelled as gas.
--- SoupGate-Win32 v1.05
* Origin: you cannot sedate... all the things you hate (1:229/2)
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