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# Ozone

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1. ## What makes mass?

umm, energy? E=mc^2 ? 6.022E23? Cheers, O3
2. ## Deionized Water

Mu guess is that it was boiled to remove dissolved oxygen. Cheers, O3
3. ## A Working Lightsaber?

When a photon exceeds 1.022 MeV, the tendency of it to undergo pair production increases. In this case, the photon will split into an electron and a positron. The positron will then annihilate (the matter converts directly to energy) with another electron (ideally) to yield two photons, in 180° directions (from one another) of 0.511 MeV. E=MC2, made real! Unfortunately, 0.511MeV is of low enough energy such that the majority (of one half of the output, considering 4pi geometry about the point-source, you being on one half of this) of its energy will likely be left inside you, in the form of hydroxyl and peroxyl radicals. Cheers, O3
4. ## A Working Lightsaber?

Whoops, I am so used to seeing these dewars filled with N2 that I forgot to explicitly point out that you would need a huge vessel of liquid argon (to get the enormous amount of gas needed). An RF coupled plasma torch is 1-2 cm in diameter. You would need a dewar (for the incarnation I have in mind) because the Ar is not recycled, it diffuses into the surrounding air once is has escaped the RF coupled region. At the flow rates needed to achieve a long torch ("beam") the time spent as plasma will be very short. The energy required to create and sustain a B field like that needed for this task would be quite large and/or require supercooled magnets (liquid helium, ~4 K, see NMR). Either way, you could not carry this device around with you. You could take some wicked photos/cut some stuff, etc. Hypothetically speaking, O3
5. ## A Working Lightsaber?

Thanks, bascule ( I needed that)! OK, sorry about the shorthand: L/min = liters per minute 3 in = 3 inches (multiply by 2.54 for centimeters) RF = radio frequency, expressed in watts (hence, power) N2 = nitrogen (l) = liquid dewar = an insulated vessel (double walled glass vessel where the interior is under vacuum) inside of a sturdy metal container which is used to store/transport liquified gasses (such as N2(l)). Hope that helps, O3
6. ## Excel 2007

The label is the box with your equation and/or corellation coefficient in it. right click on that. I just went through the order I posted previously in Excel 2007, worked fine. I agree, though about the new and more cumbersome architecture and features. Pretty? Yes. functional? Not if you are used to older versions. I've been through every version since 4 (macro language and all) and preferred XP/2003 the most (good looking with the functionality/architecture that you know and love). My biggest peeve, so far, with 2007 is that I can no longer simply ctrl-V a series into a plot. I now have to right-click-paste it in there. I prefer hot-keys so anytime I need to use the mouse (where otherwise unnecessary) it ticks me off. inefficient. Anyway, at least the plots look very nice and I have learned that calibri is a very nice font. Cheers, O3
7. ## Excel 2007

Right click on the label. Select format trendline label. Click on number from the list on the right. Put in the decimal places you want. Click on close. Cheers, O3
8. ## Organic Compound project paper

Maybe you could narrow your search down a bit. Say, biodiesel, which is a mix of esters derived from triacylglycerides. Or, you could try fragrances or flavors, or lignin or acetylcholineEsterase inhibitors... Let your fingers do the talking, let your search engine do the walking! You should find articles in no time. Do you have access to a University library? If so, the number of journals available to you is immense! Cheers, O3
9. ## Molality problem

Do not confuse molaRity with MolaLity. Here, you have both. Check the density of water, the rest should fall into place. Cheers, O3
10. ## A Working Lightsaber?

Actually, inductively coupled plasma. the "blade" length is limited to the gas flow rate (which is huge, something akin to 7 L/min ti get ~3 inches) and the RF power used to couple the plasma (once struck with a piezo electic crystal). I suppose with a huge gas supply (to get the 3"er we use a N2(l) dewar...) and a high RF transmitter (which goes through a coil orthogonal to the "blade" (torch) axis). Huge machinery yes, unwieldy umbilical, yes, four foot ICP? Yes (green if using Ar, red, Ne, white He (though very difficult to couple)). You couldn't spar with it, but it would look the part, and could certainly hack a car in-half (Light saber of life, anyone?). Heat would not be the issue. The coupling coil and quartz bonnet are mm for the torch and remain unscathed. What would get you, though, will be the *enormous* UV output. You will definitely get a tan. Oh well, they have cream for that. Muuhaahaa, and all that, O3
11. ## Virgin Atlantic to run 747 on Biofuel

I agree with you both. But, still, it's cool that a non-petroleum source of liquid fuel is involved.To lighten things up, a little, I bring you a flight to Amsterdam powered using... Amazon Nuts! http://www.reuters.com/article/topNews/idUSL2451986620080224?feedType=RSS&feedName=topNews&rpc=22&sp=true I couldn't resist. Anyway, at least it's not soybeans! Jatropha, anyone (the nuts made me think of it:D)? Cheers, O3
12. ## Virgin Atlantic to run 747 on Biofuel

I did some rough calculations for the fun-of-it. The values are mole-based and adjusted for densities, etc., but do not account for processing energy, transport or high-heating value differences in fuel types (Maybe I'll do that later). Pimentel would, no doubt, wag his finger at me! Assuming a fuel capacity of 217053 L (http://www.aerospace-technology.com/projects/747/ ) and a trip range of approximately 356 km (http://www.timeanddate.com/worldclock/distances.html?n=136 ), 20 % biodiesel (normalized to methylstearate) made from soybeans at (a conservative) 11.50 USD/bu (they broke 12 USD/bu recently) at roughly 27.2 kg/bushel (20 g/100g oil) we would need: 6985 bushels of soybeans (80,330 USD, on beans *alone*) to fill the tank (at 20 % biodiesel) or 183 bushels for the trip. Waste would include approximately 83 L of crude glycerol/trip or 3146 L/tank. Whilst I am in firm support of biofuel use wherever feasible (Thumbs-up to Virgin), these (admittedly back-of-the-napkin) calculations seem to point out that: 1. We need cheaper (and less food/land intensive) sources of oil for biodiesel than soybeans (rape will go up too). Sources may include bacteria/yeasts or algae. 2. We will be up-the-wazoo in almost worthless waste glycerol in no time. 3. We are still using lots Avgas. Thanks for the heads-up! Cheers, O3
13. ## decrease Radius of penny

I suppose you could get a hold of sme Maxwell pulse caps and put a 100kA though a thick Cu coil (with your coin inside) in a fraction of a second. Whew. example (there are many, but these are the first I found): http://www.stevehv.4hv.org/coinshrinker.htm http://205.243.100.155/frames/shrinkergallery.html I suspect that your coin shrinker would be a stronger project! Cheers, O3 Lichtenberg figures are cool too!
14. ## Have you switched to Compact Fluorescent?

I started replacing incandescent bulbs w/CFs on a "when-dead" basis. Now, nearly all of our lights are CF and I couldn't be happier. I don't need to change bulbs very often (which I hate because I am short and need to use a ladder) *and* my electric bill has been reduced by appx. 20%! This is how they need to sell these things--forget the carbon-neutral-Al gore rhetoric, Exploit our laziness and greed! Cheers, O3
15. ## Reducing sugars

Look up "cyclic voltammetry" and "pulsed amperometry". That should do it. The calories are dependent upon the DH of the material, not the REDOX potential (see mCDT). Please note that a dissacharide (or any polysaccharide, for that matter) where the hemiacetal (see anomeric carbon) is tied up with a glycosidic linkage is NOT reducing. From hence, see aldehyde, ketone, reductone, etc. Sweet! O3 Oh, yes, for further info check out tollins, Fehling's and Molich's reagents. Please see also, Laine and Eynon.
16. ## help!

Look up Jone's reagent, and chromic acid while your at it. I am quite sure that oxidation (or dehydration, for that matter) of butanol will *not* yield a compound which smells even remotely like vinegar. Hit the books, do the experiment, smell the victory! Cheers, O3
17. ## How many 5 year olds could you Fight?

Apparently, 29... Cheers, O3
18. ## HCl (aq)

HCl is a gas. It is soluble in water up to about 38%. There is a good amount of information here: http://en.wikipedia.org/wiki/Hydrochloric_acid Most of it is true. Cheers, O3
19. ## Easy Science Question

Above all, tell the truth. Even a failed experiment has provided results. Cheers, O3 Sorry about the one liner, but this can go on forever without prior composition.
20. ## What do you not like about SFN?

First, thanks for hosting the site. The only problem that I encounter (ad nauseum) is the very short time-out period (which Chemkid alluded to on the first page of this thread). I will usually get an idea, start a response, and then need to do some research (so that "pulling it out of my ass" is not so painful). Then, I will finish the post only to find that I am no longer logged in. It is possible to accidentally hose your post this way. Thanks again, O3
21. ## What energies are involved in ozone production?

The static field required to breakdown (that is, jump a spark across a 1cm gap) dry air is about 30kV. A smallish practical ozonator is the Welsbach T-23 which is capable of delivering 0.5mmole O3/minute (Murray, et. al. (1972). Ozone reactions with organic compounds. ACS Adv. Chem. Ser. 112., pp. 11). I do not know, however, what the operating potential of this particular device is. One is used here (they say 120V, but I gather that this is the voltage on the primary side): http://www.orgsyn.org/orgsyn/prep.asp?prep=cv6p0976 http://www.orgsyn.org/orgsyn/orgsyn/prepContent.asp?prep=cv5p0489 The specs on the ozonator the testers used, a Welsbach T -series are given here: http://www.welsbach.com/t-series.html I do know that they usually operate between 25 and 40kV For the electrochemical route: From the citations given it can be found that (electrochemically): 3 H2O → O3 + 6 H+ + 6 e−; ΔEo = −1.53 V and the competing reaction: 2 H2O → O2 + 4 H+ + 4 e−; ΔEo = −1.23 V (6H+ + 6e-->2H2 = 0V (NHE) An additional reaction is given by Bard and Faulkner: O2 + H2O -->O3 + 2H+ + 2e- -2.075V (vs NHE) After that it should be a matter of pushing some © of electrons around. Cheers, O3
22. ## What energies are involved in ozone production?

Wherever you have an electric discharge in air (or othe O2 bearing gas that does not contain a good amount of a quencher, like methane) you will get some ozone. Old driers contain "ozonators" which were, IIRC high voltage coronal discharge tubes (which supply the UV you need to make the ozone). They gave a "fresh scent" to the dried laundry. Since this is quantized, more than 5 ev per rxn is a waste. It looks like it can be made much more easily, though: Ibanez, Jorge G.; Rodrigo Mayen-Mondragon and M. T. Moran-Moran (October 2005). "Laboratory Experiments on the Electrochemical Remediation of the Environment. Part 7: Microscale Production of Ozone". Journal of Chemical Education 82: 1546. Retrieved on 2006-05-10. In higher concentrations it is quite noxious (in odor and tendency) and adds very readily to double bonds to form ozonides. These ozonides can be decomposed (slowly) to yield two equivalents of carboxylic acid. This is the aspect I am most familiar with. They (ozonides) can (and sometimes do) decompose rapidly, which can be in the form of a nice explosion. It appears that (I need to check this for accuracy) concentrations in excess of 10 % w/w can deflagerate if ignited: http://gcmd.gsfc.nasa.gov/Resources/FAQs/ozone.html I do not know if it will explode if confined. I suppose that in the absence of a reducible substrate (which would be impressive), this would depend upon the energy released heading toward dioxygen. I should note that in larger discharges, the NOx from the N2 in the air is usually much more debilitating than the ozone (especially with large HV gaps and tesla coils, etc.). There is surprisingly decent coverage and a reference list (avoid most of the climatic screed) here: http://en.wikipedia.org/wiki/Ozone Cheers, O3
23. ## Chemical Equation

By definition, a chemical equation involves both products and reactants; without them, equilibrium (via equilibrium constants, which are calculated) cannot be defined. Accounting for this (definition wise)... Do you want something like an oscillating reaction whereby reactants and products swing back and fourth? This way there are no ultimate "products". This seems to be the only way (minus a few catalytic cycles) whereby an equation without "products" (and I say this loosely, see above) can be done. Need the info! O3
24. ## Can You Help To Identify This Micro/Nano Object

Not nano...not even "micro". I also immediately thought mica. The color is more like muscovite, the crystal morphology is more like biotite (shown). Note the hexagonal habit. The "hairs" on the edges look asbestiform, though. I'm sticking with the mica, for now.
25. ## Elimination of methyl groups from Toluene

I too am interested in this (the soda lime is no where near basic enough to abstract a proton from toluene, unless I am mistaken?). Although not the requested, mechanism, here's one I had from a while back. IIRC, the double bond and the "six-membered" intermediate are a couple of things to look for; they make the reaction take place under much milder conditions (nevermind, in this case, the re-aromatization driving the thing). I think it may be relevant. For other examples of this sort of thing, check out the Strecker degradation whereby, in the presence of a reducing sugar (50 g/100 or so) amino acids are decarboxylated to yield the aldehyde, ammonia and CO2. For example, phenylalanine yields phenylacetaldehyde. The reaction proceeds first via the Schiff base with the carbohydrate. See also Maillard reaction and Amadori rearrangement. I have made this reaction work at 80°C. Cheers, O3
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