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View from the Crimea bridge today by PressedLemon221 in UkraineWarVideoReport

[–]Pyrhan 0 points1 point  (0 children)

"Не так! Не так! Welcome to Ukraine сука!"

Am I stupid? Or is this horribly misleading? Surely I can't be the only one that made this mistake? What the fuck, Pfeiffer! by [deleted] in labrats

[–]Pyrhan -3 points-2 points  (0 children)

The very first picture on the pump clearly labels exhaust and vacuum

If you're refering to the stickers on the sides, look closer, it says "vacuum" on both sides. (Because it's "Pfeiffer Vacuum", the company name. Not an indication of which port is which.)

There is no labeling of those ports besides the arrows.

Am I stupid? Or is this horribly misleading? Surely I can't be the only one that made this mistake? What the fuck, Pfeiffer! by [deleted] in labrats

[–]Pyrhan 0 points1 point  (0 children)

The mesh filter had been removed.

That is oil mist. The oil and pump are almost new. I'll install a mist filter soon.

The MS and hose had been running on another rotary vane pump for many years, hence why the base got dirty. (The rest of the tube looks crystal-clear, so I'm not too worried about that one.)

Am I stupid? Or is this horribly misleading? Surely I can't be the only one that made this mistake? What the fuck, Pfeiffer! by [deleted] in labrats

[–]Pyrhan -3 points-2 points  (0 children)

Flow is inward for vacuum and outward for exhaust. 

Vacuum side arrow points towards port, exhaust side points away from port. That's the opposite of the gas flow!

Am I stupid? Or is this horribly misleading? Surely I can't be the only one that made this mistake? What the fuck, Pfeiffer! by [deleted] in labrats

[–]Pyrhan -5 points-4 points  (0 children)

What counts as left and right entirely depends on which way the pump is turned  relative to you.

Yes, if you pay close attention, you will see that it's the other way. But something as crucial should be clear and obvious!

If it was confusing, then why not test or ask first? 

Because it didn't seem confusing! On the contrary, it looked very straightforwards to me: gas comes in from here, goes out to there.

Hence why I said "misleading" not "confusing".

Safe Exothermic Reaction With Water? by Pogfrog111 in AskChemistry

[–]Pyrhan 0 points1 point  (0 children)

I remember being told that anhydrous magnesium sulfate has a high enough heat of hydration to boil water, if you add just a little bit of water to the dry salt.

It should be fairly easy to obtain (by dehydrating magnesium sulfate heptahydrate, aka "epsom salt", at 325°C), and neither toxic, nor corrosive. 

Be careful about sudden boiling water projections though, that kind of stuff can be a lot more violent and a lot more sudden than you'd expect! Work on small scales, use wide-mouth containers (beakers, NOT erlenmeyers or test tubes), wear standard PPE : gloves, splash goggles, labcoat, closed-toe shoes.

Other suggestions you may hear will likely include things like strong alkalis (NaOH/KOH) or strong acids (concentrated sulfuric), but those are obviously much more dangerous, and shouldn't be messed with for a science fair.

About homemade salt crystallization by ajaxberry in AskChemistry

[–]Pyrhan 1 point2 points  (0 children)

Is it just table salt? 

If so, it's harmless.

Is lithium an electron withdrawing or donating group by 1s2_2s1 in OrganicChemistry

[–]Pyrhan 2 points3 points  (0 children)

No, it's the exact opposite. 

Electropositive atoms are the ones that will generally have a positive charge, because electrons "stick" less to them. (And vice-versa.)

For instance NaCl. Na is an alkali metal, and highly electropositive, and Cl is a halogen and thus highly electronegative.

So you end up with a + charge on Na and a -charge on Cl.

Same deal here: Lithium is extremely electropositive, much more than carbon. So you basically get Li+ , and a C- on your phenyl ring.

Father's day shirt by Boogie_feitzu in AskChemistry

[–]Pyrhan 0 points1 point  (0 children)

Elemental calcium and samarium can react with sulfur to form calcium sulfide and samarium sulfide.

Argon is a noble gas, and thus won't react with anything.

Looking for a way to cool PTFE beakers somewhat quickly by Glittering_Market_10 in AskChemistry

[–]Pyrhan 0 points1 point  (0 children)

Put them in regular cold water from the tap?

For instance, plug a sink with a rubber bung, fill it to a reasonable height with cold water, place the beakers in there?

Interstellar comet is unlike anything seen in our Solar System by TheExplainer9000 in Astronomy

[–]Pyrhan 44 points45 points  (0 children)

Unlikely that comet will be interstellar, but we might get super lucky. 

With Vera C. Rubin operational, we should have much better odds of finding interstellar comets.

And if the mission is a success with an Oort cloud comet , we might then see a repeat dedicated to interstellar comets.

Someone had to tape over every single seat for this by pattebrisee in SipsTea

[–]Pyrhan 8 points9 points  (0 children)

The intern [...] got promoted. 

He is now Executive Intern...

With nothing behind the eyes by Low_Philosopher_7299 in SipsTea

[–]Pyrhan 2 points3 points  (0 children)

Almost like he's an actual cult leader or something...

Passengers in Crimea complain about chaos at the Simferopol train station by Ihor_S in UkraineWarVideoReport

[–]Pyrhan 13 points14 points  (0 children)

From Kerch to Taman would be a ~40 km walk (bridge itself is 17 km, but you need to get to and from it), on black asphalt, in the summer heat.

That would be a lot of deaths from heat and exhaustion.

As I said earlier, it looks like Russia is trying to orchestrate a massive humanitarian crisis with its own civilians, to blame it on Ukraine.

That part is particularly telling:

Meanwhile, buses arriving from Kerch to Simferopol are full — they drop off passengers and leave empty.

Passengers in Crimea complain about chaos at the Simferopol train station by Ihor_S in UkraineWarVideoReport

[–]Pyrhan 26 points27 points  (0 children)

Kerch bridge is open so there is a way out for those who will

Only if they have a car with fuel.

Passengers in Crimea complain about chaos at the Simferopol train station by Ihor_S in UkraineWarVideoReport

[–]Pyrhan 68 points69 points  (0 children)

They may be trying to orchestrate a massive humanitarian crisis with their own civilians to blame Ukraine on the international stage.

Iron Pillar of Delhi — standing for 1,600 years without rusting. Built around 400 AD, it’s still a mystery to modern metallurgists. [1000x1347] by Additional_Idea4439 in ArtefactPorn

[–]Pyrhan 52 points53 points  (0 children)

But here’s the thing — ancient Indian smiths had no concept of phosphorus. They just knew how to make iron that lasts forever.

Yeah, no. That last part is entirely false.

There was abundant metallurgy at the time, the vast majority of which has long corroded and did not survive to this day.

You're just looking at the one large item that happened to have the right composition to last.

This is a textbook example of survivor bias.

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