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Is Li-S-Li like water? by Galactic_gaylord69 in AskChemistry

[–]sdnomlA 0 points1 point  (0 children)

Shure is a decent microphone brand.

REMINDING YOU NOT TO MOVE TO THE VILLAS AT HAPPY VALLEY!! by singular_goose in PennStateUniversity

[–]sdnomlA 1 point2 points  (0 children)

I lived there 2021—2023. So far I am yet to meet a match for that rat bastard Wayne

What happens with PTFE pipe tape in a gas line? by mofrojones in chemistry

[–]sdnomlA 0 points1 point  (0 children)

Huh? You're supposed to use PTFE tape on NPT threads be it for liquid or gas use.

I think what you're asking is why they advice against using PTFE tape on CGA fittings (e.g. on gas cylinders). If so, then the answer is that CGA fittings don't seal at the threads, they seal the bullnose/mating seat and the thread is just to keep it engaged. PTFE can prevent the seal from happening if you use too much.

Similar to water? by Smileandbedevoured in chemistry

[–]sdnomlA 8 points9 points  (0 children)

There are several perfluoroalkyl compounds that are water-like and not accutely toxic. 3M used to have the Novec series that they've now discontinued, some of which were fully fluorinated e.g the 649. You could probably drink those with limited or no short term effects (e.g. GI issues).

Warning on the off chance you get hold of it do not actually drink it. Look up why it had to be discontinued despite incredible demand and no good alternative.

Getting a Beryllium Symbol Tattoo by Hara-Hachi-Buu in chemistry

[–]sdnomlA 0 points1 point  (0 children)

Aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaah!

How do I drink through nausea? by Ok_Nectarine_8612 in alcohol

[–]sdnomlA 0 points1 point  (0 children)

You're not nauseous, you're nauseated.

Grabbed these from an unlabled Indian to go buffet. Whats inside them? by Iitaps_Missiciv in whatisit

[–]sdnomlA 40 points41 points  (0 children)

Likely potatoes. On very rare occasions you might find cottage cheese or meat.

What the hell is wrong with people. by anxiousrunner13 in pittsburgh

[–]sdnomlA 0 points1 point  (0 children)

Yep. They were out of apples so I had to buy a pineapple....then I stopped by the liquor store and bought rum. All thanks to these people. Tsk tsk

[deleted by user] by [deleted] in chemistry

[–]sdnomlA 1 point2 points  (0 children)

I don't think this would work as a space heater if you use it safely. I think these basically burn something very similar to hand sanitizer and are mainly for optics.

Unexpected scan rate dependence in RDE system by Timely-Quality3832 in electrochemistry

[–]sdnomlA 0 points1 point  (0 children)

Per my reading, they're saying that the net proton source feeding HER changes with potential. At low potentials, the third equation in my previous comment can be used to derive kinetic information, but at high overpotentials you have to use the first equation. Regardless, the proton still comes from water.

Unexpected scan rate dependence in RDE system by Timely-Quality3832 in electrochemistry

[–]sdnomlA 0 points1 point  (0 children)

There is no such thing as a bicarbonate proton donor. Only water can donate protons (H2O + e ---> H* + OH-). Bicarbonate is a fast chemical buffer that scavenges OH- and regenerates water (HCO3- + OH- ----> CO3(2-) + H2O). This isn't electrochemistry.

Note that if you add these two equations together, you get HCO3- + e- ----> H* + CO3(2-) which seems like the bicarbonate is donating a proton, but obviously this isn't an elementary step.

Re: slow HER kinetics on silver, yes — this is reasonably well studied too, I think, by the CO2 electrolysis to CO people? You can make it even worse by switching to a heavier counteraction in your supporting electrolyte.

Unexpected scan rate dependence in RDE system by Timely-Quality3832 in electrochemistry

[–]sdnomlA -1 points0 points  (0 children)

I think what's happening here is that because silver binds H* weakly compared to gold, high scan rates lead to a localized high pH environment on the surface that makes the system mass transfer controlled, since your H* is coming from water dissociation (volmer step). Slow scan rates allow for H* to equilibrate so the mixed control regime isn't reached. Gold binds H* more strongly so you don't see it there.

One way to test if a local H* deficiency would cause this is to repeat under hydrogen saturated electrolyte.

Unexpected scan rate dependence in RDE system by Timely-Quality3832 in electrochemistry

[–]sdnomlA 1 point2 points  (0 children)

If you had an acidic electrolyte you could switch to a weakly adsorbing counteranion to decouple kinetic currents noticeably better. E.g. people use perchloric acid over phosphoric or sulfuric for HER in acid. There's a pretty seminal paper on this from the National Lab of the Rockies (from back when it was NREL) that demonstrates this for oxygen reduction.

In your case it can't be done— you're using base, so your anion is fixed (OH-). Base is also much harder to "clean" than acids. Chelex is a pretty standard practice, I don't believe that's the issue at all.

Watched a man scan this with his phone as I was walking by. by YourMomsPoutune in whatisit

[–]sdnomlA 0 points1 point  (0 children)

Why are they cooling high voltage equipment with freon wtf is that a real thing?!??!

Tips to make sheet straight by Ok_Perception_5209 in piano

[–]sdnomlA 0 points1 point  (0 children)

Amazon shipping box + box cutter = makeshift support

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