John Cuthber

In space... nothing much happens. It's the blobs of stuff in space (stars, planets and so on) that are interesting. I don't think I'd pay for the extended 12 inch remix of this http://soi.stanford.edu/results/sounds.html but perhaps that's just my weird taste.

I remember the statement; it seems you can't, or you didn't understand it. Here's what I actually said in response to the assertion that only the properties of hydrogen are different between different isotopes "Only hydrogen isotopes have different chemical properties," Not quite true http://www.tandfonli...64#.Umlk__n_kao But the differences are usually only laboratory curiosities, rather than practically useful." The first thing I said was " I can't think of any applications of stable isotope substituted chemicals outside the laboratory, but that isn't because we don't know about them, it's because they are not very different from the ordinary versions and they are much more expensive." So, the first thing I did was point out that they were different- not not very different (apart from the price). The second thing I said was to point out that the differences are not only observed for hydrogen. So, lets be clear about this In the thread you cited I said that there are differences between the chemical properties of isotopes: I said it twice. In this thread, I pointed out that not all samples of an element will contain the same ratios of isotopes. That's because they have slightly different properties- as I had said a year and a half ago. Why do you think there is a "Difference like between night and day" between saying the different isotopes are different and the different isotopes are different? Anyway, would you please let me know the answer to the question I asked earlier. Here it is again to help you: how you you would actually make up a solution- say 1000 ppm m/v of sulphuric acid to such accuracy that it would be possible to distinguish between 1 in a million and 1 in 999999?

Have you noticed how few digits there are in some of these numbers? "31.972071 * 0.9493 = 30.3510870003 32.97145876 * 0.0076 = 0.2505830866 33.9678669 * 0.0429 = 1.45722149 35.96708076 * 2.00E-004 = 0.0071934162" Do you think there might be a reason for that? Do you think that all samples of sulphur contain exactly 94.93% of the light isotope? Do you realise that variations in the natural abundances of isotopes will change the measured mass- and would change how much sulphuric acid you would need to weigh out to make a 1 ppm solution to such a precision that it matters whether you add 999999 or 1000000 parts of water ? Did you really think that I'd be getting it wrong all this time? See fig 1.3 here http://dge.stanford.edu/SCOPE/SCOPE_43/SCOPE_43_1_Chp1.pdf

OK, The vacuum pumps I use most often are my lungs (pretty much all the time) and one of these In the lab I'd still make the decision based on what I want the pump for.

What Nobel Laureate? from http://en.wikipedia.org/wiki/Nobel_Memorial_Prize_in_Economic_Sciences "It is not one of the prizes established by the will of Alfred Nobel in 1895, but instead was established 73 years later by Sweden's central bank" (or was the spelling mistake deliberate?). "Most people, mainly middle-class employees, actually own stocks in their IRA's or 401k's, through Mutual Funds." I rather doubt that most people are middle class employees. For what it's worth I probably do count as a middle class employee and my pension isn't based on stocks anyway. "One of the main income sources for high-net-worth individuals is tax-free Muni bonds." Main? I'm sure it's one, but how big a component of their income is it? "One of the basic laws of economics is that the reward has to be commensurate with the risk; if it isn't, nobody, even the rich, will invest in the project" As has been pointed out twice, the very rich don't take any significant risk.

Yes, you said about one isotope. e.g. "Sulfur-32 31.97207100(15)" etc. But it's still progress! Now, all you need to do is think about this " natural abundance" and you will see why the table I cited earlier is correct (rather than "nonsense" or "What a garbage!") and why you can't state the molecular weight of his sulphuric acid to 6 figures.

Thanks for making it abundantly clear that you don't understand the reference I cited. While I could ask Swansont, on the grounds that he's a mass spectroscopist, it would seem redundant. I am also a mass spectroscopist (at least occasionally). Would you like to think about it some more? I assure you that the table of data I gave is correct. Here's a hint- do you think that the acid the original poster is asking about only contains one isotope of sulphur?

" I am doing quantum physics. We do care about precise calculations.." LOL http://en.wikipedia.org/wiki/Uncertainty_principle You can calculate as accurately as you like- but the real values are uncertain. The commercial packages for calculating masses for chemical compounds let you choose which average you want. The really good ones don't give the spurious accuracy that yours does. The molar mass of sulphur depends on where you get it from http://www.chem.qmul.ac.uk/iupac/AtWt/ so your application claims an unrealistic accuracy. There's simply not enough information to state the molar mass of the sulphuric acid to that precision. Were you not aware of this? Shouldn't you have found out before writing an app that misleads people? My method for making up a 1 ppm solution actually gave an answer that's a bit low. it gives 0.999999000000999999000000999999 ppm (m/m) Your method gives about 5.4 ppm (m/m) I'd say you are a lot further from what the OP wanted than I was. Also, if you care about precise calculations, you are in trouble here. Adding 1 ml of sulphuric acid to 1 ml of water doesn't give you 2 ml of mixture. http://www.everyscience.com/Chemistry/Physical/Mixtures/a.1265.php That's before we get to the question of how you measure a volume to a precision of a part in a million or so (unless you can do that there's no practical difference between adding 1000000 parts of water or adding 999999 parts) Also, can I ask how you you would actually make up a solution- say 1000 ppm m/v of sulphuric acid to such accuracy that it would be possible to distinguish between 1 in a million and 1 in 999999? The first step is to get the acid pure enough that you can guarantee that you know how much acid you have to that accuracy. Good luck. Anyway, it's good to see that you have realised that your first post here was wrong. You said "Any scientist and student should know how to calculate ppm to moles and grams." And it's clear that no scientist could do that (from the information available) And it seems that you agree with my first post which said "I am a scientist and I couldn't give a definitive answer"

What do you want it for?

I rather suspect that most plants are quite well earthed, so if they have a net charge they must be using energy to maintain it. I can't find the paper. is there a link to it somewhere? I'd like to see how the charge was measured.

I didn't get that far- my internet security software blocked it. I wouldn't recommend that anyone ckicks on that link

You are not participating is a discussion either.

You were the first to make a prediction based on a questionable model, when you said " we find relatively docile storm seasons around the globe as CO2 levels relentlessly creep upward". So, you opened the thread with a post that's so bad even you can't offer thanks for it.

I can invent a lot of different amino acids. if I make a polypeptide in which no amino acid appears twice is it a polymer? It's not made from a monomer. no "mer" is present more than once so there's no "poly" about it. Is a diamond a macromolecule? Is it a polymer? A lot of these depend on exactly what definition you use. I think most polymers are based on repeating monomer units- but it's not clear if that's the defining property,or just the way most of them are made.

I'm sure it's someone's "law" that, when you correct something on the internet you add mistakes of your own. We have two examples here. I said "take 1 gram of acid and dilute it with a million grams of water" When I meant "take 1 gram of acid and dilute it to a million grams with water" Well, OK, it's wrong- but it was early in the morning, and I had a bus to catch. I don't know what your first language is,but this page is in English. And current English usage is decisively ambiguous. For mixtures of gases ppm usually refers to mole fraction- but that's because it's (practically) the same as volume fraction. For solutions it's as often a "shorthand" for mass of solid dissolved in a volume of solvent that would have 999999 times that mass, if the solvent were water. So, if I dissolve 1 mg of sugar in 1 ml of alcohol it's a 1000 ppm solution. (i.e. it is micrograms per ml). Have fun with your spreadsheet. Perhaps the most important point is that the person who asked the question at the start of the thread can't expect a valid answer. He needs to check with whoever asked him to make up the solution (unless he can be sure from the context that it doesn't matter (for example, if he's just washing glassware with it.).) So, your spreadsheet is either exactly right or roughly 2 million times more wrong than I was, or something else. .

This http://www.cas.org/content/counter gives you an idea of how many chemicals have been reported in the scientific literature. (66 million or so) It's fair to assume that not all known compounds are documented (lots of pharmaceutical companies keep their data under wraps) In principle, you could search through them all looking for amino acids. I doubt that anyone has bothered. Another lower bound to the number of amino acids is to consider that essentially any protein will have free amino, an acid, groups (if only at the ends). So the purpose of every single gene that codes for a protein, is to make an amino acid. That's a lot of different ones.

It's not always Gaussian. http://en.wikipedia.org/wiki/Spectral_line#Pressure_broadening .

OK, lets have a quick look "I have considered all the above and more and am more confused than ever. " Seems like fair comment. "For example, John C, your flat assertion that the CFCs are evenly distributed is at odds with the cited explanation of preferential planetary distillation. " OK, your problem here is that you didn't actually read what I wrote. I said "The CFCs themselves are reasonably evenly distributed". For some reason you either didn't see, or didn't understand the word "reasonably". Which was it? Re. "If you are correct in this, why is the condition of the polar regions of such grave concern? ". Well, because I live on the same planet as the polar regions; perhaps more importantly, the whole of the ozone layer is in trouble, it's just a lot more obvious at the poles. Then you say "That would scare people more, which is pretty much the primary goal of the environmentalists." which is odd. The point of the my posts here (and I suspect most others) is to put forward the evidence. Your point seems to be to ignore it- fore example, you ignored the word "reasonably" in what I wrote earlier. Yet, for some weird reason you think that saying "we can avoid some of our problems getting worse if we actually do something" is a way to scare people. Nope, it's a way to offer some sort of hope. "Furthermore, given that ultraviolet radiation is responsible for the formation of ozone to begin with, isn't some sort of temporary deficiency in ozone to be expected at the polar regions after months of continued darkness" Nope, it's more complicated than that. I guess you were right when you said you were confused. Measuring ozone isn't easy. It's only relatively recently that we have been able to get accurate measurements over large areas. The first measurements from space were in about 1978. So a paper from 1980 can't have more than 2 years of good data. The 1990 paper seems to be commenting on the validity of a paper from 1958- Interesting in its way, but I can't see from the title how it relates to the topic in hand. The one from 1950 is of historical interest only. It would be interesting to see them; are they on line somewhere? Also, do you have any more recent papers? the ones that can look at the most reliable data are likely to be recent Since,as has already been pointed out, the weather also has an effect on ozone levels, the single datum from 2011 doesn't really tell you a lot. Why did you raise it,then knock it down. Was that an attempt at a straw man?

Or, do I take 1 gram of acid and dilute it with a million grams of water, or do I take a millilitre of acid and dilute it with a million millilitres of water? Unless you are dealing with gases the mass/volume interpretation is probably most common and you are wrong. If you worked here http://www.romil.com/pag_mono.htm they would tell you that you said "it's easy" then came up with a complicated spreadsheet that gave the wrong answer. The point remains- the question is ambiguous.

"But most successful business owners I know actually supply jobs to others, pay their good employees well" OK, fine, but we are complaining about the ones who pay their staff 100 times less than they pay themselves, yet still feel they should cheat on their taxes. "Well, if the Company's successful because of their talents, ... " Again, that's not the problem. Most companies "do well" as a result of luck, yet most people attribute their success to "talent" even when that's clearly not the case. "One simple solution; tie CEO pay to performance. " That's a nice idea, but how do you measure it? The problem is that, if you link CEO pay to some parameter, that's what the CEOs will maximise. "Somebody's got to take a risk" ​not much of a risk- that's what limited liability companies are for. "nor do they have enough money, to solve all the country's problems. And that last statement IS opinion, I can't back it up with facts." No. They really do have the money. Let's do a simplistic analysis. The top 0.1% of the richest US citizens own 22% of the wealth, and there are not many problems you couldn't solve with, say, 10% of that. If they paid as little as 10% tax they would hand the government 2% or so of the total wealth of the US. http://en.wikipedia.org/wiki/Financial_position_of_the_United_States that's something like 2.5 trillion dollars.Compare that with http://en.wikipedia.org/wiki/Military_budget_of_the_United_States Call it 4 times the security budget- from just 10% tax. So, you are welcome to your own opinion, but the facts don't support it.

Harold, Just to clear something up for you... DDT is a halocarbon. The PCBs are halocarbons lindane s a halocarbon Hexachlorobenzene is a halocarbon So, pretty much all the compounds mentioned here http://en.wikipedia.org/wiki/Global_distillation are, whether anyone likes it or not, halocarbons. That page also refers to persitent pollutants, and there's a well known list of a "dirty dozen" of those http://en.wikipedia.org/wiki/Persistent_organic_pollutant#The_2001_Stockholm_Convention.E2.80.99s_Dirty_Dozen Ten of those are halocarbons, and even the other two are closely related compounds. Now, what did you think your point was when you said "Seriously, does anyone think that the devious little(but heavier than air) halocarbon molecules migrate to the poles like arctic terns before wreaking havoc? I mean, anyone SANE? "? Actually, I don't care. The damage to the ozone hole over the Arctic isn't particularly due to a raised local concentration of CFCs there. It's due to the weather- specifically this http://en.wikipedia.org/wiki/Polar_stratospheric_cloud giving rise to conditions where the CFCs really trash the ozone. The CFCs themselves are reasonably evenly distributed so your whole point was a red herring. BTW, if you don't like WIKI, feel free to check out the references it gives.

In fairness, the question is so ambiguous that I rather hope it isn't homework. I am a scientist and I couldn't give a definitive answer so I'd love to see how Sensei thinks he can. Over to you...

Fair point, feel free to do a better job. The real killer was that Sensei posted those figures without taking account of the fact that the US simply has more tax to evade, so it's almost bound to get more evasion. And there are certainly factors in common like those you suggest. I was just pointing out that the weak correlation didn't prove (or, even, strongly suggest) anything

Zet, This " The demagnetized state is a higher energy state than the magnetized state." is just wrong. Yes I disagree with them. Domains form spontaneously, but bar magnets don't There's also an "activation"energy associated with getting the domains to randomise. That's why it happens faster for hotter magnets. If you want to generate a magnetic field, you need to supply energy. Destroying the field releases energy, sometimes violently. http://en.wikipedia.org/wiki/Superconducting_magnet#Magnet_quench

Guess again, unless you think that things spontaneously roll up hills. Since you have the direction of the energy change wrong it's no wonder you think the energy changes don't add up.