User talk:Sadi Carnot
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[edit] Chemical elements found on Earth: answer is at least 94
Hi, please provide a source for this edit. My references state 92 naturally occuring elements. --Sadi Carnot 00:47, 2 March 2007 (UTC)
- Perhaps there's a rule against for using wikipedia as its own source, but for stuff that's obvious, I don't think it's more than a simple problem of putting in the work to get a cite, which at this point I don't have. But there's no element up to Np (number 94 inclusive), which isn't found naturally on Earth, as you can see by reading the Wikis on all the elements with lower atomic numbers. So you can count, and the number is 94. I have no idea where the classical 92 number comes from in all the old books-- are they just mechanically going up to U and forgetting Tc and Pm? Or going up to Np and leaving out 43 and 61? Or maybe 85? and leaving in Tc or Pm? I dunno, and I don't care. But the number is 94. In the case of Np, it's found in trace amounts in U ores, having been formed by neutron capture. If you read down in the chemical elements article to the discovery section, it gives the 6 rarest ones on Earth, starting with the rarest, astatine, followed by Fr, then the others (Pm and Tc found first in stars but later verified naturally, and Pu-244 actually found pimordially). If you look up the individual Wikis on all these elements (start with astatine, where it's a major part of the interest) you'll see the details. Some are referenced, but if Isaac Asimov said it, you can google it. SBHarris 19:37, 2 March 2007 (UTC)
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- According to the 2004 Oxford Dictionary of Chemistry, there are “92 naturally occurring elements.” Likewise, according to the 2004 McGraw-Hill Concise Encyclopedia of Chemistry states that all elements with atomic numbers above 92 have been synthesized in a variety of man-made nuclear reactions. Google search results for “number of naturally occurring elements” likewise indicate 92 as the common answer. I would prefer exact sources and dominant views. I will move this discussion to Talk:Chemical element where the change to "94" occured. --Sadi Carnot 20:05, 2 March 2007 (UTC)
[edit] Unneeded cat
Are you talking about "rm unneeded cat sort tags"? Another editor added sort keys identical to the article title to many physics articles. This is undesirable, since it prevents the category sort order from adjusting if the articles are later renamed.--Srleffler 06:49, 7 March 2007 (UTC)
- Thank you. This sounds reasonable. --Sadi Carnot 13:39, 7 March 2007 (UTC)
[edit] Non-covalent bonding
I'm puzzled by your removal of the merge tag from non-covalent bonding with the reason "non-covalent bonding is important in the field of supramolecular chemistry according to Lehn". I'm not questioning the importance of non-covalent bonding. What I'm questioning is whether the Wikipedia articles currently titled non-covalent bonding and intermolecular interaction actually deal with different topics. My opinion is that they don't, and therefore having two articles is redundant. I don't have a strong preference regarding the title of the resulting article, though. --Itub 12:33, 12 March 2007 (UTC)
- While I appreciate your effort to organize, I have interest in supermolecular chemistry and although one could loosely merge these without to much difficulty, I reason that they should remain separate. Although I need to read more in this area, from what I understand so far Jean-Marie Lehn, the main founder of this field, who won the 1987 Nobel Prize for his work in SMC, defines “molecular chemistry”, as begun by Friedrich Wohler in 1828, as related to the making and breaking of covalent bonds. He contrasts this with the new field of “supramolecular chemistry” as related to the making and breaking of non-covalent bonds between supermolecules. Intermolecular forces, on the other had, is a more general term which may include the covalent bond if fashioned so. If you don’t believe me, look at this edit by User:V8rik, in which the intro definition of supramolecular chemistry is defined by the use of the term “noncovalent bonding. I hope this helps? --Sadi Carnot 00:26, 13 March 2007 (UTC)
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- Let's continue the discussion in Talk:Noncovalent bonding for more visibility. --Itub 08:51, 13 March 2007 (UTC)
[edit] Real and Imaginary...
You made some edits on the thermodynamics page about real and imaginary boundaries. I don't think you actually explained what is meant by those terms. To me, it read a little like "it can be A or B. A is A and B is B". Perhaps you could expand? --Jdpipe 00:59, 3 April 2007 (UTC)
- Hi, Jd. Yes those terms could use some more clarifying; however, that particular contribution was made by an anonymous user prior to my edit, I was just cleaning it. I’ll see if I can think of some good clarifying examples over the coming days. Basically, however, the “boundary” is simply an imagery dotted line drawn around the volume of a something in which there is going to be a change in the internal energy of that something. Anything that passes across the boundary that effects a change in the internal energy of that something needs to be accounted for in the energy balance equation. That “something” can be the volumetric region surrounding a single atom resonating energy, such as Max Planck defined in 1900, it can be a body of steam or air in a steam engine, such as Sadi Carnot defined in 1824, or it can be the body of a tropical cyclone, such as K. Emanuel theorized in 1986, or it can a single nuclide, i.e. a system of quarks, as some are currently theorizing presently. Later: --Sadi Carnot 01:24, 3 April 2007 (UTC)
