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Contents 1 260 Gigagrams Produced Annually 2 Equilbrium Constant of Hydrazine 3 Asymmetric dimethylhydrazine 3.1 Reference for "tobacco and cigarettes" statement 3.2 fire triangle 3.3 B-Stoff redirect 3.4 Excess and semi-random safety info

[edit] 260 Gigagrams Produced Annually

Added a small conversion to kilograms afterwards for the lay reader who probably has never heard of gigagrams! —Preceding unsigned comment added by 78.32.32.105 (talk) 13:01, 21 February 2008 (UTC)

Gigagrams?!? Give me a break! You should give such industrial volumes in Metric and English Tons (e.g. 260,000 Metric Tons or 286,000 U.S. Tons), unless you really intend to measure it down to the gram. —Preceding unsigned comment added by 130.76.96.17 (talk) 19:36, 21 February 2008 (UTC)

[edit] Equilbrium Constant of Hydrazine

What is the equilibrium constant for the formation one mole of hydrazine? And what's the equation?

Chemical reaction for formation of one mole of hydrazine from its elements:

N₂ + 2 H₂ → N₂H₄

I don't know what the value of the equilibrium constant would be. H Padleckas 21:06, 11 Jun 2005 (UTC)

The value of the eqm constant has to be determined experimentally and varies with temperature, so you'd need a detailed data book. 202.155.218.91 04:16, 21 January 2006 (UTC)

For the equilibrium

then K_c =

and is measured in mol^-2 dm⁶. K_p is the same formula, but with P_X instead of and is measured in atm^-2. ThomasWinwood 19:24, 20 November 2005 (UTC)

[edit] Asymmetric dimethylhydrazine

Both dimethylhydrazines are in fact symmetric when viewed properly (CH₃NH-NHCH₃ and CH₃-N₂H₂-CH₃), so the name "asymmetric hydrazine" doesn't make sense to me. If it is chemical jargon, which of the two dimethylhydrazines is called asymmetric? Why?
—Herbee 07:57, 1 Oct 2004 (UTC)

• 'Cause they're not both symmetric. You listed the same isomer twice.

CH₃-NH-NH-CH₃ is symmetric, but (CH₃)₂N-NH₂ is not (well, not along the same axis). Clear? DS 16:45, 17 Oct 2004 (UTC)

• • You're right. Just by looking at the physical structure of the two varieties of dimethylhydrazine, it ought to be obvious that one of them is symmetrical and one of them is asymmetrical. In the first case, the methyl groups are attached to different nitrogen atoms, and in the asymmetrical case, they are attached to the same nitrogen atom. Not to see this is just a lack of ability in geometrical thinking. I suggest that you go back and take geometry all over again.

[edit] Reference for "tobacco and cigarettes" statement

The phrase "Found in chewing tobacco and cigarettes." is not a complete sentence as would be desirable in Wikipedia. Also, is there a reference for this statement? Such a reference might provide concentrations of hydrazine present. Although hydrazine is not very volatile, it is slightly volatile. Maybe a process for removing volatiles (such as airing out the tobacco) might get rid of the hydrazine in the tobacco. H Padleckas 20:51, 11 Jun 2005 (UTC)

Moreso, is it present in tobacco leaves, or only formed through combustion? I'd very much like to see a reference for this - TCallahan

• It is well-known that ammonia is found in tobacco, and so, hydrazine, being so chemically-related to ammonia, is very probably found there, too.

• Smoking tobacco IS aired out in flues, where it is heated with lots of air. Please look up the subject of tobacco "curing".

• Hydrazine in NEVER formed during combustion. It ought to be clear from elementary chemistry, that when burned in an atmosphere containing plenty of oxygen, hydrazine is destroyed by being converted into nitrogen gas and water vapor: the chemical formula would state that one molecule of hydrazine plus one molecule of oxygen yields one molecule of nitrogen plus two molecules of water. Further examination would reveal that this reaction is energetically favored and it quite exothermic. Hydrazine is used as a rocket fuel, for Pete's sake, and it is reacted either with oxygen or with oxygen-containing compounds like nitrogen tetroxide (N2H4).

The hydrazine plus nitrogen tetroxide reaction is also hypergolic, which means that it occurs, energetically, without any ignition source.

Anhydrous ammonia (ammonia w/o any water) plus liquid oxygen is also a rocket fuel, but it requires ignition. This mixture was used by the X-15 rocket plane program, which made 199 flights.

[edit] fire triangle

whats the NFPA 704 for hydrazine? is it similar to the one for ammonia? mastodon 01:35, 3 December 2005 (UTC)

[edit] B-Stoff redirect

It is inappropriate to redirect B-Stoff to Hydrazine, as the B-Stoff used in the V-2 project was actually an ethyl alchol/water solution. I'm setting up a disambiguation page in the redirect's place. --Adamrush 16:01, 5 July 2006 (UTC)

[edit] Excess and semi-random safety info

This article is pretty crude chemically and has excess acretion of safety information. The article is not about the toxity of this very useful chemical, but should alude to that as a modest size component of the overall report. A similar discussion has been held at http://en.wikipedia.org/wiki/Talk:Aniline --Smokefoot 23:09, 11 August 2006 (UTC)

Yeah, that's a pretty widespread problem with articles about chemicals. Institutions are required to have MSDSs of the materials they use, therefore MSDSs are widely available sources, therefore they are used for Wikipedia articles, therefore the articles tend to focus on all the bad things the chemicals can do to you rather than why they are interesting or useful. —Keenan Pepper 15:45, 13 August 2006 (UTC)

I agree though specific references to health effects are relevant. The information about the satellite being shot down was particularly random and irrelevant so I removed it. 15.243.169.73 (talk) 19:55, 15 February 2008 (UTC)

Yet the problems of safety of their use on satellites will bring many people to this article. We should at least acknowledge this in the article, either to conform this concern or to refute them (citing authorities and sources, of course) SaintCahier (talk) 20:34, 15 February 2008 (UTC)

I don't agree that the satelllite is relevant nor that it is a good example; it is just sensationalism. More relevant would be leakage in rocket fuel pipelines that contaminates ground water or trucks carrying hydrazine that get into accidents on the freeway; though I would not recommend documenting all of those instances either. We are not trying to popularize this subject so it gets more hits or list any annecdotal incidents in history that may involve hydrazine. If you add every incident, the valuable information gets lost in a bunch of fluff. When people hear about hydrazine in the media, this page will get hits. When hydrazine is not in the media, the page will receive visitors who mostly care about the chemical and not about the fluff. In addition, the original satellite comment was just saying that the US government said hydrazine could cause problems when I think the remainder of the article already makes that point. If someone wants to start a "hydrazine incidents" article with a bunch of trivia, maybe that can happen (although wikipedia frowns upon trivia sections) --Futurerichperson (talk) 23:50, 15 February 2008 (UTC)

The only reason this page is getting any hits at all is because it's in the news. Otherwise, Hydrazine is a boring nitrogen compound.70.61.22.110 (talk) 21:58, 20 February 2008 (UTC)Newt

Not sure what I'm doing here, but wanted to add my two cents about the satellite issue.

My take on this is that the danger of hydrazine is being used as a ruse by the government in order to justify shooting down the satellite, probably because of the possibility that someone will get their hands on it and find out about classified technologies and programs. In fact, this was the reason given in some news broadcasts; shooting the satellite down has many more and riskier consequences than spilling 1000 kg of hydrazine, even in the middle of New York. In fact, the US was on China's case for shooting down a satellite half the size of this one, and blowing it up in space is going to create a new major amount of orbiting debris which will endanger other satellites as well as manned missions. Perhaps someone more knowledgeable than I about these topics could look into this and temper the statements made about the danger of the satellite's hydrazine, rather than simply parrot what appears to be government propaganda. 76.229.85.16 (talk) 06:10, 16 February 2008 (UTC)

As hydrazine is being reported widely in the media in connection with this satellite case then some reference, government conspiracy or not, should be made to it. Imagine if it did crash to earth and hydrazine poisoned some people then it would be something worth mentioning. So may as well start the entry now. If nothing else, the beryllium-lined fuel tank connection is an interesting bit of practical knowledge. —Preceding unsigned comment added by Troll King (talk • contribs) 12:29, 16 February 2008 (UTC)

Agreed, some reference should be made; however, it would be best to quantify the risks to assist in evaluating the probability that the government story is credible, as opposed to propaganda. I have now seen that the Russians are claiming that this is in fact a ruse to justify testing of US anti-satellite weapons. Given that the article touts many beneficial uses of hydrazine, and on scales involving orders of magnitude more of it, the relative threat should be brought into perspective. In the past the US has allowed satellites containing many kilos of plutonium to re-enter and crash with little or no media fanfare, for instance. 76.229.85.16 (talk) 23:36, 16 February 2008 (UTC)

The whole publicized worries about hydrazine in satellites is quite silly. Hydrazine BURNs in air at high temperatures, yielding nitrogen gas and water vapor. Re-entering satellites are sure-as-hell hot. The tanks containing hydrogen will burst upon re-entry, and shooting the satellite with a missile will double-insure this. What one needs to be concerned about is large metal sections, such as aluminum-magnesium alloy I-beams, and large pieces of heat-resistant composites, surviving the high temperatures of re-entry. Shooting the satellite and reducing it to thousands of pieces of scrap will reduce the probability of this happening greatly. —Preceding unsigned comment added by 74.249.76.120 (talk) 21:34, 17 February 2008 (UTC)

Pieces of debris from a low-orbiting satellite will not form clouds of long-lasting "space junk". There orbits will decay just like the orbit of the satellite will, and even more rapidly. Low-orbiting pieces of space junk re-enter and burn up in the atmosphere all the time, and they are rarely even noticed. There is a simple physical law that guaranties that small pieces decay faster than large ones: smaller pieces have a higher ratio of surface area to mass. Thus, they have a higher ratio of drag by the exosphere to their kinetic energy. Hence, they do not last very long in low orbits. —Preceding unsigned comment added by 74.249.76.120 (talk) 21:44, 17 February 2008 (UTC)

Plutonium is rarely used in Earth satellites, and there is a good reason for this: there is plenty of solar energy available to be collected by solar cells. Also, there is a BIG DIFFERENCE between hydrazine in a lightly-built fuel tank, and plutonium in a heavily-armored package for generating electricity, which is commonly-used in space probes to Mars (the two Viking landers), Jupiter, and beyond. This plutonium is heavily-armored, and deliberately so, with layers of metal and extremely-tough composite materials. Why? NASA wants to insure that the plutonium (or any other radio-isotope) is completely-contained in case of any launch failure. The plutonium is also the isotope Pu-238, which has a much shorter half-life, and gives off a lot more heat, than the more-common and longer-lived isotope Pu-239, which is the one that is usable in nuclear weapons and nuclear reactors. (The word for this is "fissile": it undergoes rapid chain reactions when enough of it is gathered together. Most other isotopes aren't fissile. The other three well-known ones are uranium-235, U-234, naturally-occurring, and U-233, which is made from thorium.)

There were also radio-isotope-powered thermal generators for electricity for the Apollo Lunar Surface Experiment Packages (ALSEPs) that were planted on the Moon by the Apollo landing astronauts with their LEM. Of course, Apollo-13 never made it to the surface of the Moon, its ALSEP never left the LEM, and the LEM did re-enter the Earth's atmosphere along with the CSM (Command and Service Modules). Everything in these burned up, except for the Command Module (CM) containing the three astronauts, and the sealed and armored radio-isotope thermal generators, which came through the atmosphere and was deposited onto the bottom of the South Pacific Ocean. It's still down there, and nobody has bothered to look for it. There isn't any reason to, other than historical curiosity.

DAW

From years ago, I remember some discussion re: the Dodge Boys (1960s Chrysler factory sponsored drag racing team) was severely called down because of their use of hydrazine (or perhaps a derivative) as an "exciter" agent added to nitromethane instead of the methanol commonly used. Supposedly, the rub came after the mix sat for about an hour and became a class-a explosive. Does anyone else remember this or is it just my 60s growing up period rearing its head? Frank, Broken Arrow OK—Preceding unsigned comment added by 70.177.114.130 (talk) 07:56, 19 February 2008 (UTC)

The text above sort of proves the point that the reference to the satellite is largely irrelevant to the chemical article, that it is currently a fad topic that encourages people who cannot prove relevance to post (as opposed to daily transport via pipelines and trucks that have a higher potential saftey impact), and then there are the conspiracy theorists. Give it a year and no one will care about the satellite any more, but for now, don't pollute the article. Futurerichperson (talk) 16:41, 19 February 2008 (UTC)

In the sentence "The presence of a thousand pounds of hydrazine has been cited as the reason that malfunctioning US spy satellite 193 will be shot down in late February 2008.", I think they even have it backwards. The missle contains the hydrazine (as its fuel) and not the satellite. The concern I've heard (undocumented) is that 1000 pounds of it are in the missle and some may come back through the atmosphere. I agree it is not appropriate unless someone comes up with true references through. This article will probably get significant exposure in the next day and may need "Temporary semi-protection". Bobtheowl2 (talk) 01:57, 21 February 2008 (UTC)

It has been pretty clear in the stories that I've read that the 5000 lb 'bus sized' spy satellite USA 193 contains 1000 lbs of hydrazine propellant. The fuel is used for retasking the satellite, but since it never became operation the tanks were never used or depleted. The SM-3 missile that was used in this shootdown is normally powered by a solid fuel motor, although I have heard that this particular missile was modified but no details about the modification. Amcarroll32 (talk) 14:58, 21 February 2008 (UTC)