Talk:Sulfonate

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Sulfonic acids as strong acids[edit]

I have made a change to the article. It previously stated that sulfonic acids tend to be strong acids, so the conjugate sulfonates are weak bases. This is erroneous on two accounts, first, only one sulfonic acid is strong, and that is sulfiric acid, the rest are weak (to my knowledge, feel free to correct me if I am mistaken). Secondly, the conjugate base of a strong acid is not a weak base, it is not a base at all, but rather neutral (e.g. the halide ion from strong hydrohalic acids, or the nitrate ion). I am not sure if it is even worth mentioning in this article about the relationship between acids and bases, it seems simpler to me to just note that sulfonates are weak bases and leave it at that.

Thank you, 50.15.180.1 (talk) 15:22, 14 June 2012 (UTC)[reply]

The article was correct. Sulfonic acids in general are strong acids. Their conjugate bases are weak bases, as is the case for other strong acids. ChemNerd (talk) 16:45, 14 June 2012 (UTC)[reply]
Doing a little research, it seems you are half correct. I was unaware that sulfonic acids were strong, however, unless I am mistaken, that would mean that the pKb of sulfonates would be above 14. Is that not the definition of a weak base, that the pKb falls between 0-14? 50.15.180.1 (talk) 20:51, 14 June 2012 (UTC)[reply]
I guess another way to clarify my point is to say that a strong acid would dissociate completely in water, by (one) definition. An (anionic) weak (Bronstead) base will, some small percentage of the time, abstract a proton from water to form a neutral compound and the hydroxyl anion. If sulfonates that were conjugates of strong sulfonic acids were to abstract a proton from water, they would then form a strong acid which would then immediately dissociate. Does this not preclude the conjugates of strong acids from being weak bases? If not, how are these things compatible? I am looking to understand sulfonate chemistry as this is a new area to me, and I just want to make sure I have the complete picture. 50.15.180.1 (talk) 21:14, 14 June 2012 (UTC)[reply]
It's a matter of semantics, I suppose, whether you want to call sulfonates weak bases or to say that they are so weakly basic that they are not really bases at all. Not all sulfonates are going to have exactly the same basicity, anyway, so they will fall along a spectrum and referring to them collectively as weak bases makes perfect sense to me; but it shouldn't be seen as some kind of absolute. ChemNerd (talk) 11:30, 15 June 2012 (UTC)[reply]
Okay, that makes sense then, I suppose my confusion has to do with the definitions I was given for weak and strong, which seem to be a) different than wikipedia's and b) much more of a black and white thing than wikipedia's. I appreciate you clearing that up for me. 50.15.180.1 (talk) 13:39, 15 June 2012 (UTC)[reply]

is it worth distinguishing sultone from sulfone (which has own wiki page) given similarity in name? — Preceding unsigned comment added by 203.13.3.72 (talk) 02:18, 15 July 2016 (UTC)[reply]