Wikipedia:Reference desk/Archives/Science/2010 September 25

= September 25 =

Yellow jacket wasp, death of nest in winter
I understand that yellow jacket nests usually die in the winter.

How long does it have to be cold and what temperature is cold enough before I am reasonably sure the nest has died? I live in the Sierra Nevada foothills of California and am avoiding a certain valued trail because I am allergic. (Don't worry; I carry an EpiPen.) —Preceding unsigned comment added by Ahatch (talk • contribs) 01:12, 25 September 2010 (UTC)
 * Your friendly neighborhood Park Ranger or Forest Ranger would probably know or be happy to help you find out for your region and the wasps in question, even if the particular nest your are concerned about isn't in their exact area of operation. Wiki Dao  &#9775;  (talk)  02:49, 25 September 2010 (UTC)


 * It's hard to find definite information, but the impression I get from looking around a bit is that yellowjackets can stay alive in their nests in temperatures down to freezing or even below, but they become pretty lethargic when the temperature drops into the 50's. Looie496 (talk) 04:37, 25 September 2010 (UTC)
 * My personal experience with yellowjackets is that they buzz around aggressively a lot, but rarely actually sting. In fact I don't think I've ever been stung by one, though as a little boy I was stung by hornets with similar coloring.
 * Not that I'd count on that if I were allergic, certainly. Ahatch, I'm sure you know that an EpiPen is not a substitute for immediate medical attention, which might not be available on the trail. --Trovatore (talk) 02:09, 26 September 2010 (UTC)
 * I'd generally take 'I have an epipen' as code for 'I have a truly serious allergy, but I am responsible and well-informed, so please do not lecture me on safety or worry too much about my decision-making abilities.' I've seen it used this way several times by people living with lifelong allergies when they were ordering in a restaurant, or asking a company a question about their factory, or even just trying to move a conversation on. 109.155.33.219 (talk) 18:16, 28 September 2010 (UTC)

Angular nodes and nodal planes
what is the difference between angular nodes and nodal planes?? are they the same?? the number of angular nodes in an orbital is equal to the azimuthal quantum number. and the number of nodal planes is also equal to azimuthal quantum number.. so, are they both same?? harish (talk) 03:06, 25 September 2010 (UTC)
 * I think that "angular node" and "nodal plane" are different nodes, though both are related to the principle AND azimuthal quantum number. If you look at File:HAtomOrbitals.png, you can see radial nodes and planar nodes.  The radial nodes are apparent in the 2s, 3s, and 3p orbitals, while the planar nodes are apparent in the 2p, 3p, and 3d orbitals.  I think that the term angular node refers to the spherically-shaped radial nodes which are concentric to the nucleus, while the nodal plane runs through the nucleus.  My quantum chemistry knowledge in this area is about 12 years rusty at this point, however. -- Jayron  32  04:28, 25 September 2010 (UTC)
 * For an atom, an angular node and a nodal plane are the same thing. You usually say "angular node" if you want to distinguish them from "radial nodes". "Nodal plane" is more common when you're talking about bonding, so you often find it in introductory descriptions of atomic orbitals as well: a σ-bond has no nodal planes, a π-bond has one nodal plane and a δ-bond has two nodal planes. Physchim62 (talk) 08:37, 25 September 2010 (UTC)

Fire in Zero Gravity
Well the title is pretty self-explanatory, how would fire look, better yet behave in zeo-gravity, say, a space ship. 66.229.227.191 (talk) 12:19, 25 September 2010 (UTC)


 * Here you go http://www.youtube.com/watch?v=fuFftT6ZR4k ny156uk (talk) 12:23, 25 September 2010 (UTC)
 * That's a fairly long-winded video answer from a person in space who can't light a match due to safety rules. Here's a shorter video-answer http://www.youtube.com/watch?v=SZTl7oi05dQ - the cool concept here is that the flame forms a sphere since there's no gravity to cause the less-dense hot air to rise, but this results in smothering of the flame, because without convection no oxygen is brought in (e.g. from "below") to provide necessary reagents for continued combustion.  -- Scray (talk) 14:14, 25 September 2010 (UTC)


 * (awesome video, by the way!) With the caution that since there isn't any convective transfer of heat away from the once-burning match, it will take some time to cool below its autoignition temperature. If a new supply of oxygen is introduced – either the hot object is moved to fresh air, or our astronaut stirs up the air by moving around the space ship or turning on a ventilation fan – the match will burst back into flame and burn until it again exhausts its local supply of oxygen. TenOfAllTrades(talk) 16:18, 25 September 2010 (UTC)

I want to increase the melting point of Butter.
I am on a vision to create a certain type of ghee (butter oil) which has a melting point approximately greater than 50 degrees Celsius (323 K) But natural ghee (butter oil) start melting normally at 30-32 degree celsius (room temperature). Can any one suggest me any chemical which can help me sort out the problem. Please specify the chemical name, its common name, chemical formula and its proportion to add in the natural ghee (butter oil) per kg. —Preceding unsigned comment added by Cma290193 (talk • contribs) 12:48, 25 September 2010 (UTC)
 * I am not sure where you live, but I would be rather uncomfortable in a 30-32C room for an extended period of time. Googlemeister (talk) 13:22, 27 September 2010 (UTC)
 * Hydrogen, along with a catalytic amount of Adams' catalyst: the exact quantities will need to be determined by experiment. Physchim62 (talk) 15:06, 25 September 2010 (UTC)
 * Does this sound like a homework question? Wiki Dao  &#9775;  (talk)  17:16, 25 September 2010 (UTC)
 * You might not even need the hydrogen. The platinum catalyst alone may promote isomerization of the double bonds in the unsaturated fats, giving you trans fats that can have a higher melting point.   Bromine might do the trick, too.  I don't know if anyone has ever made the ghee-derived equivalent of brominated vegetable oil before.  Maybe you could even patent the idea and make a lot of money by selling it to ADM.  —Preceding unsigned comment added by 96.227.210.71 (talk) 16:32, 25 September 2010 (UTC)
 * But if you intend this for human consumption, don't add bromine, or form trans fat or branched fatty acids, as these all have health negatives. Perhaps you can add a gelling agent, but it would make this ghee hard to digest. Graeme Bartlett (talk) 21:53, 25 September 2010 (UTC)
 * Yea, butter is already >60% saturated fat so I'm not sure saturating the rest would make that much difference to the melting point. You'd need to make the fatty acids longer through elongation reactions to seriously raise the melting point, which you can't do with simple chemicals. What exactly are you wanting to use it for? Palm oils are naturally longer chained than butter (which is why they've replaced hydrogenated fats) so maybe use these instead. Smartse (talk) 22:02, 25 September 2010 (UTC)
 * Butterfat is already mostly saturated. If you turned it into completely saturated fat, I suppose the melting point would go up, but I don't know if it would go up that much. It would be (mildly) interesting to know, from a chemical perspective, but as Graeme says, don't feed the stuff to me. --Trovatore (talk) 22:01, 25 September 2010 (UTC)
 * Why didn't I get an edit conflict?! Smartse (talk) 22:03, 25 September 2010 (UTC)
 * That's happened to me a few times recently too; don't know why. Looie496 (talk) 22:47, 25 September 2010 (UTC)
 * The software has automatically resolved edit conflicts for several years now. It doesn't always work well, but it's often okay. I don't know how much it has changed over the years, but people have been commenting on no EC for probably 2 years at least on the RD Nil Einne (talk) 16:37, 26 September 2010 (UTC)
 * I don't think there is actually any chance of getting an edible fat with melting point 50 C. Nothing in current use gets within a mile of that. Looie496 (talk) 22:47, 25 September 2010 (UTC)


 * Please don't feed me an oil with a melting point above body temperature! Ariel. (talk) 06:06, 27 September 2010 (UTC)


 * What about a gelling agent like agar? It sets at room temperature, but undergoes hysteresis and only melts at around 80C. I'm not sure if the agar will be soluble in melted butter though. Maybe you need to add egg whites. John Riemann Soong (talk) 06:49, 27 September 2010 (UTC)

Sauces with cornflour or wheat flour
When making a sauce, is there any advantage to using cornflour rather than wheat flour? Does cornflour cook more quickly, or have any other advantage? Thanks Edit: Cornflour is apparantly referred to as Corn starch in the former colonies. 92.28.241.137 (talk) 14:43, 25 September 2010 (UTC)
 * Yes, you use corn flour to thicken the sauce. The normal procedure is to wet the corn flour with a small amount of water or milk and then add it to the sauce near the end of the cooking: heating the mixture will cause it to gel, giving a thicker sauce. Wheat flour is usually used at the start of cooking a sauce, to adsorb fatty falvour components and stop them being lost. The two are not interchangeable: using corn flour instead of wheat flour will give you a lumpy suace (always a risk when you use corn flour), while using wheat flour instead of corn flour will give a sauce which is too liquid. Physchim62 (talk) 15:00, 25 September 2010 (UTC)
 * This sums it up better Thickening Agents - Flour and Making a Roux--Aspro (talk) 15:25, 25 September 2010 (UTC)


 * (EC)Cornflour is much higher in starch than wheat flour, and doesn't contain gluten. The starch is the thickening agent, the same as is used in blancmange and custard powder. For a starch-thickened sauce or pudding, cornflour is generally what you want: you would have to add more wheat flour for the same effect, and that would come with more other components, like gluten. 109.155.33.219 (talk) 15:28, 25 September 2010 (UTC)


 * Please disregard what the non-chefs are saying. Either corn or wheat flour will give you a lumpy sauce when used incorrectly; they must be fully hydrated in order to gelate the starch. The main advantage of corn flour over wheat is that it thickens more quickly, and does not render a sauce opaque when doing so. Both corn and wheat flours must be cooked, however, to remove the raw starch flavour. Wheat flour is not used to 'absorb fatty flavour components and stop them being lost;' it is used as a thickening agent via creation of a roux. The two are in fact largely interchangeable, and the notion that wheat flour will produce a sauce that is too liquid is, well, bizarre. It depends entirely on how much you use. Corn flour has the added advantage of not going 'gluey' as it cools. Essentially, you can use either one you like, it just depends on what you want your end result to be. → ROUX   ₪  17:17, 25 September 2010 (UTC)


 * Here's an idea - citing a source - On Food and Cooking says that corn flour is practically pure starch, whereas wheat flour is ~75% starch, meaning that corn starch is a more efficient thickener. Because adding a thickener to a sauce dilutes the flavour, corn starch may be used if the chef wants to make a sauce as intense as possible. During the manufacturing of corn starch it is milled wet though which can give it flavours that wheat flour doesn't have. On the other hand, the gluten in wheat makes the sauce opaque and matte which a chef may not want it to be, so they may wish to use corn flour if they want a clearer sauce. Starch is an immensely complex molecule, containing different amounts of amylose and amylopectin, depending on the source. Sauces created with them have different properties - wheat sauces gel at 52-85°C whereas corn starch sauces do at 62-80°C. Wheat sauces are more stable after prolonged cooking than corn sauces but cannot be as thick. In short - there is no distinct advantage in using corn starch - it depends on what you're making and wheat is normally fine in my experience most of the time (original research). (You can also use arrowroot starch, potato starch and tapioca starch depending on the dish.) Smartse (talk) 22:32, 25 September 2010 (UTC)


 * A major part of the thickening effect of a wheat-based roux comes from the gluten. With all respect, if you think that wheat-flour-based sauces can't be as thick as cornstarch-based sauces, you probably haven't made one.  It's quite easy to make them so thick that they're impossible to stir. Looie496 (talk) 00:45, 26 September 2010 (UTC)
 * Seriously. If you are using the exact same amounts by weight of cornstarch and wheat flour, the cornstarch will provide a thicker end result, but if you used equal amount by weight of e.g. methylcellulose, you would end up with something almost solid. (This also depends on whether you are using a roux, and if so, whether you are using it blonde or dark; the latter has more flavour but less thickening power). In addition, I--ps, I'm a professional chef--have found not a whole lot of difference in flavour loss between corn and wheat; starches absorb and sequester flavours, period. That being said, cornstarch mutes brighter flavours less than what does, which is why one sees cornstarch so frequently used in dessert fillings. In terms of other thickeners, one would actually get better (less loss of flavour) results with thickeners such as xanthan gum, methylcellulose, carrageenan, or even agar (all depending on your intended temperature of course). The statement that wheat sauces cannot be as thick as corn sauces is blatantly and completely false and wrong. → ROUX   ₪  02:53, 26 September 2010 (UTC)
 * It's somewhat odd to me that cornstarch (called cornflour right of the Pond) is being compared with wheat flour. Surely the apples-to-apples comparison would be wheat flour versus cornmeal, or wheat starch (does anyone make that?) versus cornstarch.  --Trovatore (talk) 03:00, 26 September 2010 (UTC)
 * No, it's a perfectly apt comparison. Think of it along the lines of, say, 'would I want to use red wine vinegar or balsamic vinegar in this dish?' Both wheat and corn flour are ground portions of part of the kernel. Corn meal is, conversely, the entire dried and then ground kernel, and is not used for thickening; it is used in breading, to provide a crispy layer, in polenta, and in baked preparations such as cornbreads. → ROUX   ₪  03:27, 26 September 2010 (UTC)
 * I think cornstarch has had something else done to it, no? I don't think it's just the ground grain; I think the starch has been carried off with water or something, and then dried.  I don't know that for sure but that's what I always thought.
 * Put it another way: You can make bread out of flour, and you can't make it from cornstarch, therefore cornstarch is not flour, whereas cornmeal is. --Trovatore (talk) 03:36, 26 September 2010 (UTC)
 * Ummm... no. Like I said: both wheat and corn flours are made from part of the kernel. Corn meal is the entire kernel. Like wheat flour, cornflour/cornstarch is largely made of starch. Unlike wheat flour, it contains no gluten. One can indeed bake with cornstarch, you just need to adjust your recipes to allow for the lack of protein. Cornstarch in baking provides a significantly crispier product, though is not suitable for all applications, and usually cannot be used solely by itself. → ROUX   ₪  03:39, 26 September 2010 (UTC)
 * Ah, here, from our article:
 * The corn is steeped for 30 to 48 hours, which ferments it slightly. The germ is separated from the endosperm and those two components are ground separately (still soaked). Next the starch is removed from each by washing. It is separated from the gluten and other substances, mostly in hydrocyclones and centrifuges, and dried.
 * Clearly this is not how you make flour. Of course our British friends are perfectly at liberty to call it cornflour if it gives them pleasure, but it isn't flour.  Whereas cornmeal is. --Trovatore (talk) 03:41, 26 September 2010 (UTC)

Dude... look, I'm going to say this in a really nice way, but you have no idea what you are talking about. See flour, to begin with. In technical terms, cornmeal is a flour, yes. But in practical applications in the kitchen, cornstarch is much closer to 'flour' than the meal is. I'm not really sure why you're arguing a linguistic variation. The British call potato chips 'crisps' and French fries 'chips.' Should we tell them they're wrong about that, too? → ROUX   ₪  03:47, 26 September 2010 (UTC)
 * I have seen flour. It says flour is made by grinding up cereal grains.  Cornstarch is not; it's made by washing the starch away from the flour and then drying it. --Trovatore (talk) 03:50, 26 September 2010 (UTC)
 * Oh boy. *facepalm*. You... well, you can just go ahead and complain about the use of language as much as you like. After my weekend I'll be getting back to a professional kitchen where I use corn flour all the time, and corn meal all the time, for entirely different applications. You're welcome to believe what you wish, after all, why would an expert in the field know anything? Sheesh. → ROUX   ₪  03:57, 26 September 2010 (UTC)
 * As an aside, in response to the question above by Trovatore, wheaten cornflour does exist at least here in NZ Nil Einne (talk) 04:03, 26 September 2010 (UTC)
 * That link redirects to gluten, which seems misleading at best. Maybe someone wants to do something about that?  I wouldn't know where to start, myself, unless just to retarget it to starch.
 * @Roux: I'll try to bring down the emotional level a notch here.  I can believe that wheat flour and cornstarch might serve similar roles in sauces, which judging from your username is a special interest of yours.  But I think you have to admit they really don't, in baking.  You say you can bake with cornstarch but admit that it's not usually satisfactory by itself.  Whereas corn meal bakes up into a very lovely, if somewhat crumbly, bread.  In that sense, surely, corn meal is closer to wheat flour than cornstarch is.  --Trovatore (talk) 04:15, 26 September 2010 (UTC)
 * Except that it's not. The reason why what flour is so useful in baking is the presence of gluten, which creates a protein-starch matrix in which the other ingredients, and especially air, are suspended. Cornmeal has no such action. Corn starch, on the other hand, does (partially) create such a matrix when used in baking. → ROUX   ₪  04:25, 26 September 2010 (UTC)
 * Please stop with the exasperated tone, OK? It isn't polite, and I made an effort to get back to civil discourse; I think you can too.
 * Now, on the substance, can you really make bread just from cornstarch? I have never seen it.  Where would one encounter it?  Secondarily, apparently cornmeal does have gluten (the cornstarch article specifically mentions separating the starch from the gluten) so why exactly would corn meal not make this matrix of which you speak? --Trovatore (talk) 04:29, 26 September 2010 (UTC)
 * I am exasperated because you keep harping on the same thing over and over and not listening to what you are being told. I do not know the exact science behind why cornmeal does not have that action, though I suspect it is that there is relatively very little gluten in corn and thus it is too weak to hold together. McGee, This, or Adria would probably be able to give you a definitive scientific answer to the question. And yes you can make bread-like-things just from cornstarch, they just don't rise as much, and run the risk of burning very quickly. → ROUX   ₪  04:34, 26 September 2010 (UTC)
 * OK, well my exasperation comes from the attitude you have taken even after you were proved wrong about the origin of cornstarch. --Trovatore (talk) 04:38, 26 September 2010 (UTC)
 * Except you did no such thing, so not sure where your exasperation comes from. In any case, after your particularly ill-advised and rude questioning of my credentials, without an apology, it seems abundantly clear that I am being sucked down a rabbit hole of endless IDHT. I am withdrawing from this discussion; you are welcome to believe what you wish. → ROUX   ₪  04:48, 26 September 2010 (UTC)
 * Fair-minded readers can judge for themselves. I do apologize for the remark about the credentials, which I self-reverted quickly.  However I did indeed prove Roux wrong about the cornstarch. --Trovatore (talk) 08:05, 26 September 2010 (UTC)
 * No, you did not. As I stated, cornstarch is made from part of the kernel--the starch. The fact that I didn't go into the precise details of manufacture is supremely irrelevant. I wasn't going to respond, but I will not let lies about me stand uncontested. → ROUX   ₪  08:39, 26 September 2010 (UTC)
 * The record is right above us, Roux. I said I thought the cornstarch had had something else done to it, that it had been carried off with water and then dried.  You said "no".  It's true, there were other things you could have been saying "no" about, but you certainly didn't clarify.  I found the article passage that described how cornstarch is made, which was exactly as I had said.
 * That was the point at which you told me "nicely" that I didn't know what I was talking about.
 * As I say, fair-minded readers can judge for themselves. --Trovatore (talk) 08:45, 26 September 2010 (UTC)
 * If you say so. → ROUX   ₪  09:00, 26 September 2010 (UTC)

Although I'm sure it wasn't fun for you two. I, for one, found this entire argument interesting. Both of you: Please don't be dissuaded from continuing to contribute. And maybe someone can tell me why potato starch makes much "gluier" pudding than corn starch. Ariel. (talk) 06:04, 27 September 2010 (UTC)
 * For what it's worth, I also found the information provided by Roux to be interesting. --Trovatore (talk) 06:09, 27 September 2010 (UTC)

As the OP, on reflection what matters most to me is which one is easist to get rid of the floury taste? Wheat flour or cornflour/starch? Thanks 92.29.116.227 (talk) 10:58, 27 September 2010 (UTC)
 * Cornflour. As stated above, mix it with a little water or other liquid suitable for cooking and you can add it quite near the end of cooking. Stir in a spoonful at a time because if added all at once it can go lumpy. Wheat flour needs to be cooked through for longer. Itsmejudith (talk) 15:01, 28 September 2010 (UTC)

Can you make water from Hydrogen & Oxygen?
Is it possible to take Hydrogen & Oxygen and turn them into water directly? E.g I have a tank of Hydrogen (gas or liquid) and a tank of Oxygen (gas or liquid) - is there a way to cause a reaction between them that will turn them to water (rather than a massive explosion!) Exxolon (talk) 16:06, 25 September 2010 (UTC)
 * All it takes is a spark to convert a mixture of H2 and O2 into H2O. Heat is generated.  Whether or not you get a massive explosion or not will be determined by how much of the mixture you put a spark to.  —Preceding unsigned comment added by 96.227.210.71 (talk) 16:10, 25 September 2010 (UTC)


 * You could do it with a hydrogen fuel cell.  --Aspro (talk) 16:11, 25 September 2010 (UTC)


 * The name hydrogen actually means "water making" in Greek, and was named such because it was noted in the 18th century that burning hydrogen gas (with oxygen) produces water. --Mr.98 (talk) 16:17, 25 September 2010 (UTC)


 * Strictly speaking, the 'massive explosion' is the reaction that turns hydrogen and oxygen into water. As Aspro notes, hydrogen fuel cells separate the reagents and catalyze the formation of water, with the added bonus of extracting some usable electricity from the reaction.  For a lower-tech solution, burn a mixture of oxygen and hydrogen under controlled-flow conditions.  Oxyhydrogen flames are used in certain types of welding and glassblowing; one should be able to condense the water vapor from above the flame. TenOfAllTrades(talk) 16:37, 25 September 2010 (UTC)
 * Thanks for the answers. Schoolboy error, forgetting that the reaction already creates water vapour with the side effect of heat/explosion. I was looking for how to control the reaction, so if you were in space for instance with abundant supplies of both gases and wanted to safely create water for say terraforming purposes. Exxolon (talk) 16:40, 25 September 2010 (UTC)
 * The fuel cells of the Apollo Command/Service Module were designed to collect the water produced; the crew used this 'waste' from their fuel cells to supplement their onboard water supply. TenOfAllTrades(talk) 17:29, 25 September 2010 (UTC)
 * Video of the reaction Wiki Dao  &#9775;  (talk)  17:24, 25 September 2010 (UTC)

Relativity
Why is Newtonian gravity incompatible with special relativity? I know it has to do with a simultaneous action, but does something acting simultaneously on something else lead to paradoxes in special relativity? 74.15.136.172 (talk) 18:46, 25 September 2010 (UTC)
 * Yes -- in special relativity, whenever something travels faster than the speed of light in one inertial reference frame, there are other inertial reference frames in which it goes backwards in time. Looie496 (talk) 19:14, 25 September 2010 (UTC)
 * As I've recently had a few opportunities to point out, that in itself is not a problem. You don't get paradoxes from coordinate-system-based backwards causality.  You get them only from real backwards causality; that is, from causal loops.
 * To get a causal loop out of this effect, you have to do the trick twice. See tachyonic antitelephone. --Trovatore (talk) 22:08, 25 September 2010 (UTC)
 * Newtonian gravity is also incompatible with other aspects of modern physics, notably the Standard model. Acording to modern physics, all forces require a Force carrier, and gravity has none.  If there is no carrier to transmit the force of gravity, then it isn't a force.  Rather, it is a pseudoforce, see Fictitious_force.  In other words, gravity is caused not by a force, but by perturbations in space-time caused by mass.  This is the core of general relativity.  There are hypothetical theories which include the Graviton in them.  Many people will tell you that the graviton has not been disproven; rather that it just has zero evidence for it, unlike the other force carriers, for which there is evidence.  -- Jayron  32  00:52, 26 September 2010 (UTC)

You can actually derive what Jayron32 says from considering problems with instantaneous action. We now don't focus on potential problems posed to causality, rather on conservation of momentum. Suppose we have two massive objects interacting with each other via some potential. If in one frame momentum is conserved, then that means that the change in mometum of one object during some time interval dt is balanced by an opposite change of the other object during exactly the same time interval.

In another frame, these momentum transfers that exactly balance each other transform into different momentum transfers and they happen at different times. This means that you cannot have conservation of momentum in all frames in general. The only way conservation of energy and momentum can be saved is if you only allow local interactions. I.e. if an object is to lose energy or momentum, it has to transfer it to something that is in direct contact with it. Interactions between objects can then happen via force fields which can carry energy and momentum. Count Iblis (talk) 01:32, 26 September 2010 (UTC)

Neat, thanks. 74.15.136.172 (talk) 02:41, 26 September 2010 (UTC)

Bleach and detergent
Would mixing bleach (Sodium hypochlorite) with a detergent for use for cleaning be a bad idea? 92.24.182.184 (talk) 19:29, 25 September 2010 (UTC)
 * I don't think so. Lots of laundry detergents include some bleach.  Of course you wouldn't want to be cleaning anything that bleach itself would damage that way. Looie496 (talk) 19:34, 25 September 2010 (UTC)
 * I wouldn't recommend it if the detergent contains ammonium though! —Preceding unsigned comment added by 24.92.78.167 (talk) 01:44, 26 September 2010 (UTC)
 * A piece of soap and sodium hypochlorite would be no problem, but if the detergent is not a pure detergentand additionally contains ammonia or even worse hydrogenperoxide there is a good chance to produce some very unpleasant reactions. nitrogen trichloride or chlorine gas are only two possibilities.--Stone (talk) 07:26, 26 September 2010 (UTC)

Dehydrated water
Could appropriate proportions of liquid oxygen and liquid hydrogen make a greater volume of water? In other words, if you added together the volume of these liquid gases, then converted them to water, allowed it to cool to room temperature and pressure, would the volume of the resulting water be more or less than total volume the liquid gases they came from? Thanks 92.24.182.184 (talk) 19:37, 25 September 2010 (UTC)
 * This was asked back on 10th March 2010, and the answer was no. It's not possible to compress hydrogen enough, let alone the oxygen to go with it. CS Miller (talk) 19:49, 25 September 2010 (UTC)