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Joined 2 years ago
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Cake day: June 29th, 2023

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  • ornery_chemist@mander.xyztoMemes@sopuli.xyzWhy
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    8 hours ago

    For those who did a search only to get back pages of less-than-useless SEO slop that just recites the number line, here is something that better describes some of the grammatical insanity.

    also, czterydzieści cztery is imo one of the less pronounceable words (well, two of them) in Polish.



  • Yes, on the rare occasion I cook meat. Too unpracticed otherwise. I originally got one because I’m colorblind and was scared of undercooking red meat and tired of eating leather. As a bonus, I used it to get the temperature right when I got into fancier teas and inadvertently trained myself to judge the temperature of water pouring into my mug by the sound it makes within a couple °C, which is kinda neat. Now, if I could figure out how to do something similar so I stop overcooking food, that’d be grand…


  • I know that this is partially a joke, but I was trying to figure out what kind of lab would be done to produce chloroform that would be appropriate for students (recent OSHA crackdown on chloromethanes notwithstanding)… haloform reaction I suppose? Is that a common teaching lab experiment?


  • My mom took my little brother to participate in a child psych study like this when he was a toddler (mom had some ties to the university). It was a very similar experiment with skittles as the prize. My brother sat staring glumly at the candy the whole time. The test administrator was increasingly enthusastic with praise after each round right up until the end when she congratulated him and said that he could have the whole bag. He said “no thanks” and ran back to mom crying because he was told there would be candy but they only had skittles, which he very much did not like (and for that matter still doesn’t). The administrator was apparently embarrassed and told my mom that she thought that all kids liked skittles…



  • I realize (and you mentioned) that sugar is not a well defined term, but calling degradation products of ethanol in gas “sugars” is still a bit of a stretch. Ethanol by itself usually forms some combination of acetaldehyde, acetic acid, 2-carbon peroxides, and CO2 (i.e. not sugars) upon autoxidation, though those species can react with other components of gasoline to form the precipitated “gum”. The structure of gum in the literature is pretty hand-wavy (high MW materials kinda just be like that sometimes) but tends to be much more more oxygen-deficient than conventional “sugars” (polysaccharides) even for ethanol blends and contains a wider variety of substructures. Though, I have seen some papers talking about certain microbes that can ferment the ethanol in gasoline, possibly via sugars, but I don’t think that’s the common degradarion pathway for a mower.


  • According to my buddy who worked for Dow, part of these “savings” apparently was taking a hatchet to their R&D segment with a bunch of spray-and-pray layoffs (apparently a common happening these days). I realize Dow is mostly commodity chemicals these days which is much more preservative in nature than other segments of the chemical industry, but even so it sounds like they are killing any hope of competing with new technologies and moving to the “squeeze as much as possible out before it goes tits up” stage.









  • 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.



  • ornery_chemist@mander.xyztoScience Memes@mander.xyzFlowchart for STEM
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    10 months ago

    Aqua regia ain’t no piranha, and also ain’t the most concerning thing in my post lol.

    Ah bromime. Super dense, low MW, and low bp, all making dosing accurate amounts a heroic feat. If you store your bromine cold, you can precool the pipette by sucking up and spitting out a few times before transfering, which helps cut down the vapor.


  • ornery_chemist@mander.xyztoScience Memes@mander.xyzFlowchart for STEM
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    10 months ago

    That’s just bad management / just put it on high vacuum

    Yes. The whole thing is satirizing the “Safety -> Against” bit. Each piece, though exaggerated for effect, has a basis in something I’ve seen over the years.

    Regarding NMR tubes though, the answer in my old group was precious metal complexes, which have a tendency to mirror out once they’ve done their bit. Or just existed for too long; a lot of them were touchy. The mirror tends to resist solvents and scrubbing. Nitric acid alone sometimes was enough to remove it depending on the metal, but often not. At some point the cost, effort, and danger are all supposed to outweigh just binning the lot and buying new tubes, but my PI was allergic to buying new things.


  • Like, so what if we store our tBuLi with other low-flash point flammables? And pyrophoric oxidizers? In the same bin? That’s stuck in a block of ice because in the 30-year-old freezer because it hasn’t ever been de-iced?

    What if the power goes out for a long period of time and the tBuLi goes for a swim? Or we say you have to de-ice the freezer?

    Haha sounds crazy. And, I wouldn’t have to do the shitty quench before disposal. Or work on that project anymore.

    Because you’re injured or because PI fires you?

    Haha, yeah :)

    :|

    :)

    :|

    Oh, while you’re here, does this still smell like DCM? I can’t tell if I rotavapped it all off and the NMR tubes all need aqua regia (sorry my b).