Timeline for Why will CuSO4 solution be acidic?
Current License: CC BY-SA 3.0
13 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| May 4, 2016 at 17:25 | comment | added | hBy2Py | @Jan You're right, it's pretty boring. The various hydroxyl complexes only come into play if you add base. DavePhD's answer is pretty much all there is to it. | |
| May 4, 2016 at 10:48 | vote | accept | CowperKettle | ||
| May 4, 2016 at 0:13 | history | tweeted | twitter.com/StackChemistry/status/727652356909891586 | ||
| May 3, 2016 at 18:58 | answer | added | DavePhD | timeline score: 7 | |
| May 3, 2016 at 18:38 | comment | added | hBy2Py | @Jan Exactly why I'm pressing the issue. It could be just as boring as you and Ivan have laid out. But, it might not be. I have some literature on which to fiddle -- I will probably be posting an answer either way sometime soon. | |
| May 3, 2016 at 18:33 | comment | added | Jan | @Brian I’m pretty sure that they can be neglected at first approximation (and possibly even at second) because of the significantly higher $\mathrm{p}K_\mathrm{a}$ value of $\ce{[Cu(OH)(H2O)5]+}$. But as I learnt from aluminium complexes there might actually be some fascinating chemistry in there. | |
| May 3, 2016 at 18:31 | comment | added | hBy2Py | @Jan Wouldn't $\ce{Cu(OH)2}$ precipitation and higher hydrolysis forms potentially also need to be considered? (They might prove negligible, yes, but...) | |
| May 3, 2016 at 18:29 | comment | added | Jan | The question does indeed boil down to the $\mathrm{p}K_\mathrm{a}$ value of $\ce{[Cu(H2O)6]^2+}$, which I don’t know off the top of my head but should be greater than seven. The remainder is basic maths. | |
| May 3, 2016 at 18:21 | comment | added | hBy2Py | @IvanNeretin Do you know the magnitude of the $\ce{Cu^{2+}}\mathrm{-}\ce{OH-}$ stability constants offhand? In general I agree, it's likely to be acidic, but I wonder if it's a closer thing than it first seems. | |
| May 3, 2016 at 18:17 | comment | added | Ivan Neretin | Still, that's strong enough to make the overall result acidic. | |
| May 3, 2016 at 18:15 | comment | added | hBy2Py | @IvanNeretin $\ce{HSO4-}$ isn't a strong acid; $\mathrm pK_\mathrm a \approx 2$. | |
| May 3, 2016 at 17:59 | comment | added | Ivan Neretin | There is nothing complicated about it. A salt formed by a strong acid and a weak base will make the solution acidic due to hydrolysis. | |
| May 3, 2016 at 17:25 | history | asked | CowperKettle | CC BY-SA 3.0 |