John Cuthber

I'm really not a flat earther but... If the air was replaced by some gas with a slightly higher density and refractivity, you would be able to shine a light beam round the world. The air near the surface is denser than the air further up because of gravity. The air is thin at the tops of mountains etc. There's no argument bout that. And the refractive index rises with density. So light traveling through air near the ground is slightly slower than light going through air higher up. That means that a beam of light bends down slightly- it's a bit like a mirage https://en.wikipedia.org/wiki/Mirage In the right conditions, you could get the light beam to bend downwards at exactly the right rate to keep going round the world.. https://en.wikipedia.org/wiki/Novaya_Zemlya_effect

That's a matter of perspective. You intend to dissolve gold. In fact it will dissolve a lot of metal oxides (zinc, iron etc) So you will use huge amounts of a moderately toxic chemical, mainly to dissolve stuff you don't want. Might still be an improvement on the use of mercury...

400 bar is 40 Mpa That's 40 MJ/ m3 or 40 KJ/ litre 25 litres per minute at that pressure is 40,000 * 25 i.e. 1 MJ/ min 16.7 KW of power at 100 % efficiency. At any credible efficiency it's not going to be the pressure that causes problems, but the temperature rise will set stuff on fire. What are you planning to do with about 20 horsepower of compressed air?

What flow rate are you looking at? For a few ml/min you can use a 2nd hand HPLC pump. However, remember that a 6 KPSI liquid reservoir that bursts just spills oil and makes a bit of a mess, but a vessel containing air at that pressure is a bomb. The pressure won't affect the oil.

Am I the only one wondering what happened to the rest of the Greek alphabet?

I can't help wondering what Melania's definition is. I doubt we will ever know, which rather undermines this thread. They worked out the difference between friend and foe. Trump, on the other hand, has invented a difference between friend and friend so that nobody notices who the real foe is. As you say .

At least "actually" isn't actually wrong.

Why is that happening? Oh, I forgot, it's government policy. https://www.washingtonpost.com/blogs/answer-sheet/post/texas-gop-rejects-critical-thinking-skills-really/2012/07/08/gJQAHNpFXW_blog.html

It's interesting that, as these are phased out, the same idea is being used to do a different job (on a smaller scale) https://en.wikipedia.org/wiki/Gas_holder

Without collaboration is is rock solid certain that civilisation and technology would not develop. Competition is more or less the opposite of cooperation. The usual way to defeat bullies is not that bollocks about "standing up to them". (That just gets you beaten up) The solution is ganging up on the bullies. People who are given to cooperation are, therefore better placed to defeat bullies. So, for bullies to succeed, one thing they will seek to do is to reduce cooperation among those who they want to exert power over. A way of doing that is to set them in competition with eachother. So, for example, if you tell the low paid workers that their enemy isn't the billionaire but the immigrant... It's not an absolute thing- the best you can say is that encouraging collaboration drives down bullying and drives down competition.

That seems unlikely given that breweries have been (carefully) using the same strains of yeasts for decades or more. However, if you needed a fresh supply, there's no need to trouble the animals, just wait a while with a bucket. https://www.jstor.org/stable/25031792?seq=1

Except that it means something different. Specifically, it's an insult to the Hawaiian language to say that it's phonemes are "least", rather than that they don't use many.

None of that box will reflect UV well. Did you understand this bit of what I said?

Given the yellowish colour of that card, I would say it will absorb UV . If it was white card (or maybe blue) I'd expect it to reflect it. The problem is that you can't see UV so it's hard to tell

Does this help? https://www.sigmaaldrich.com/catalog/product/aldrich/r350893?lang=en&region=GB Why do you want an IUPAC name for it?

It's a radioactive atom. It will decay; once. There will be a brief flash of light. But there won't be any indication of the path the molecule was following when that flash happened.

Fewest. (Well, it's a discussion about words..)

If you just want to count words should you bother with all the variations? If I know the verb "walk", I can deduce some of the variations "walks" "walked" "walker" etc I'd need to learn the use of "walk" as a noun, separately. But from that, I can deduce a plural- "walks" If I was counting the words in a language with a view to choosing one to learn, I might not need to count the words like "wugs" which I'll never need to remember because I can "create" them when needed. But do I count walk(v) separately from walk(n)? Perhaps I should. To the extent that there's a rule in English for making verbs into nouns, I should go to a walking, in the same way that I go to a meeting. It looks very much like the answer to the question "Which language has most words" is "it depends" BTW, since the title of the thread lacks a question mark, it is a statement. So what's "which language"?

No, you won't.

Yep. Just make sure it's a randomly chosen spectroscopist.

Mainly wrong. For a start https://en.wikipedia.org/wiki/Infrared_spectroscopy#Liquid_samples Also, re" We are only interested in motion that can lead to translation (ie evaporation) and that is the first one on my list." No If you look at a simple molecule like water you can calculate (quite easily) the number of possible vibrational modes it has. Each atom can move in any of 3 directions, (x,y and z). There are 3 atoms in a water molecule. So there are 3X3= 9 possible ways in which the atoms can move. But three of those correspond to rotations while (and here's the important bit) three of them correspond to translations. So there can be no more than 3 vibrational modes for water- it absorbs (fundamentally) at just 3 wavelengths. https://en.wikipedia.org/wiki/Infrared_spectroscopy#Number_of_vibrational_modes So the movements that you are interested in- the translations- are definitely not vibrations. (Just in case you are wondering, for linear molecules where rotating about the axis of the molecule isn't defined, there is one less rotational motion and thus 3n-5 possible vibrations.) Actually, what you want is a variable restoring force- if it varies linearly with distance you get a sinusoidal vibration. Molecules have bonds. Those bonds behave (classically) as if they're springs.

Yes they do.

"Do molecules below the surface of the liquid evaporate?|" Usually, but... https://en.wikipedia.org/wiki/Cavitation

Vole = rearranged love letters. Yes and no...

All of them; but by proxy.