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Cake day: June 29th, 2023

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  • The intended joke is that hypervalent iodine compounds like Dess-Martin periodinane flip between different oxidation states like you often see for transition metals. As an example, the mechanism usually drawn for oxidations by DMP is similar to those drawn for PCC/Jones reagent, where the electrons removed from the substrate are “banked” at the metal center. Obviously, redox chemistry is not at all limited to transition metals, but I am often surprised at iodine’s propensity to engage in it. A lot of research over the past decade or two has also developed redox catalysis with these reagents, reactivity which is commonly (though again not always) the purview of transition metals.






  • So I found this website that lists specific heat capacities for various foods, and while it doesn’t list “snacks”, dry foods values seem to range from 0.3 to 1 cal•g-1•K-1 = 0.0003 to 0.001 Cal•g-1•K-1. Assuming no phase change (i.e., melting) and otherwise temperature-invariant heat capacity, the energy required for heating a 100 g snack from freezer temps (-18 °C) to body temp (37 °C) is 1.65 to 5.5 Cal. More realistically, we can compare to eating an ambient-temp (20 °C) snack; that difference is only 1.1 to 3.8 Cal… in either case, the difference is negligible, generally < 1% of the calorie count of the snack itself.





  • I think the biggest difficulty when starting out is that you don’t know common endings and syllable structure, and so it can be hard to parse where the morphological boundaries lie. It’s much easier once you understand those, though you will still find instances where two components are combined in an unintuitive (for the learner) way, particularly if the translation maps to a (apparently) indivisible root in the learner’s language.



  • Löschen can also mean to offload cargo from a ship…

    I did not know this one either, and it seems even more different from delete/erase/extinguish. I had to look this up; wiktionary says that the unloading sense is actually from a different root (MND lössen, cognate with “los”), which may have changed due to association with the “erasure” sense, particularly in the context of erasure from ship inventories and logbooks.

    Also, thank you for the context. This kind of detail tends to be extremely difficult to search for.







  • ornery_chemist@mander.xyztoScience Memes@mander.xyzProblem?
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    4 months ago

    Good rule of thumb: if someone else hasn’t solved the problem yet, it’s more complicated than you’re assuming. If the problem is worth solving, other people smarter than you have almost certainly attempted the easy “solutions” already, and they were inadequate to solve the problem. Heck, even if it’s not worth solving, there’s a non-zero chance that some pre-Reagan weirdos took a crack at it with bonus mercury and thallium compounds for the lulz and published it all in a vague 200-word comm in a now-defunct journal.