Talk:Q415812

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has part (P527)hydroxyl (Q104116)[edit]

w:polyol: "A molecule with more than two hydroxyl groups is a polyol, e.g., with three is a triol, one with four is a tetrol and so on. By convention, polyols do not refer to compounds that contain other functional groups. Cellulose is a polymer with many alcohol groups, but it is not usually discussed as a polyol".--Fractaler (talk) 18:20, 13 January 2018 (UTC)

@Fractaler: I'm not sure what is the problem, you're trying to signal here? This is unsourced en.wiki statement. First thing is that it's not obvious that compounds should have at least 3 hydroxyl groups to be classified as polyols. It can be 2 (and then you can place polyols as an opposition to monohydric alcohols), it can be many more (depending on the source, as AFAIK there is no IUPAC definition). Secondly, IUPAC definition of diols refers to any compound that have two hydroxyl group (what's more: not necessarily alcoholic) – so limiting this class to compounds with only hydroxyl groups may not be correct. Last but not least, check correspoding category in en.wiki – there are many compounds that do not match this definition. Keeping the definition of compound with two or more hydroxyl group (without conditions that hydroxyl groups should be the only functional groups) is IMHO better than limiting it to unsourced en.wiki definition. Wostr (talk) 22:25, 13 January 2018 (UTC)
@Wostr:compound with two or more hydroxyl group: but here was: min quantity 2. --Fractaler (talk) 11:20, 15 January 2018 (UTC)
@Fractaler:, yes, but with minimum quantity (property constraint) (P2313) which was incorrect property. I tried to find correct one, but it seeme there is no such property (start time (P580) is only for dates, in quantity (P1114) you have to specify number not range). Wostr (talk) 13:37, 15 January 2018 (UTC)
@Wostr: Why incorrect? Examples of using here. --Fractaler (talk) 13:44, 15 January 2018 (UTC)
@Fractaler: these are not examples, but incorrect uses. Everything you need is description in minimum quantity (property constraint) (P2313) itself. And this qualifier can be used only in Wikidata property (Q18616576). Wostr (talk) 13:54, 15 January 2018 (UTC)
Can you add an example (to minimum quantity (property constraint) (P2313)) of the correct use? --Fractaler (talk) 14:05, 15 January 2018 (UTC)
The good example is e.g. here: pKa (P1117), but I don't know how to add this as an example to minimum quantity (property constraint) (P2313), sorry. Wostr (talk) 15:43, 15 January 2018 (UTC)
Do you mean here, for example, +minimum quantity (property constraint) (P2313)? Or here, here, or where?--Fractaler (talk) 16:13, 15 January 2018 (UTC)
minimum quantity (property constraint) (P2313) can be used only in other properties, not in items, because it's qualifier being 'property constraint'. So the correct example is:
using minimum quantity (property constraint) (P2313) in items is just incorrect, because this qualifier is not created to be used in items (only in properties, like all property constraints. Wostr (talk) 17:05, 15 January 2018 (UTC)
So, subject item of this property (P1629) in minimum quantity (property constraint) (P2313) is incorrect: minimum (Q10585806) "lowest or smallest value or item in a set" (any set, here no constraints). --Fractaler (talk) 17:24, 15 January 2018 (UTC)