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260 Gigagrams Produced Annually[edit]


Added a small conversion to kilograms afterwards for the lay reader who probably has never heard of gigagrams! —Preceding unsigned comment added by (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 (talk) 19:36, 21 February 2008 (UTC)

The English ton (2240 lbs) is not the same as either the US ton (2000 lbs, IIRC) or the metric tonne (1000 kg (2,204.62 lb)). (talk) 13:03, 10 May 2011 (UTC)

Equilbrium Constant of Hydrazine[edit]

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. 04:16, 21 January 2006 (UTC)
For the equilibrium
then Kc =
and is measured in mol-2 dm6. Kp is the same formula, but with PX instead of and is measured in atm-2. ThomasWinwood 19:24, 20 November 2005 (UTC)

Asymmetric dimethylhydrazine[edit]

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.

Reference for "tobacco and cigarettes" statement[edit]

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.

fire triangle[edit]

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

B-Stoff redirect[edit]

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)

They are confusing it with M-SToff, which was hydrazine hydrate + methanol. DonPMitchell (talk) 06:30, 1 September 2008 (UTC)

Excess and semi-random safety info[edit]

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 --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. (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. (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. (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 (talkcontribs) 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. (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 (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 (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.


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 (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)

I posted a reference to an IEEE article on the danger of (frozen?) hydrazine[edit]

I am sorry if this reference short-circuits the discussion page. The article seemed to be authoritative, even if it supported the administration's decision to fire the missile to destroy the satellite. It does contain the suspiciously non-relevant comment that some tiny meteorites are cold when they hit the earth. It also seems to claim that the hydrazine is in a solid state.

Hydrazine is highly toxic and dangerously unstable, and is usually handled as 60% (saturated) aqueous solution for safety reasons.[edit]

As I know, hydrazine is completely miscible with water. So, a saturated solution does not exist. FK1954 1:56, 1 January 2009 (CET) —Preceding unsigned comment added by (talk)

Hydrazine is also used in reactor water in nuclear power to keep oxygen levels from getting too high.[edit]

Happened to look at a recent US Dept of Energy correspondence course in Chemestry (found on Scribd) tonight. Ionizing radiation can cause water to break apart water molecules causing free radicals, excess hydrogen, and excess oxygen at times. The Hydrazine is apparently added to the boiler water to keep it from getting too much oxygen and promoting rust. Maybe someone should mention the nuclear connection with boiler water? WonderWheeler (talk) 10:03, 23 April 2009 (UTC)

Ok, hydrazine is used in reactor plant coolants to scavenge oxygen when the reactor is shutdown for long periods of time. During normal operation, the oxygen is controlled by the use of dissolved hydrogen gas that is added to the primary system. I can only speak to military reactor plants, as I have not operated commercial power plants. Hydrazine is added to the secondary boiler water for the same reason, to scavenge oxygen, except that the boiler water is never subjected to a gamma flux and requires a chemical means to remove oxygen. Hydrazine was chosen over traditional boiler chemicals like phosphates because it will carry over with the steam and not build up in the steam generators like non-volatile phosphates. On the ship I was on, we never used hydrazine controls in the primary. The plant would have to be shut down for months to get the gamma flux so low that hydrazine would be required instead of hydrogen gas. Nblanton 01:15, 02 May 2009

Good point. I didn't mean to imply that the chemical is added all the time, sorry if I left that opinion. Only used in certain circumstances AFAIK. WonderWheeler (talk) 07:09, 14 May 2009 (UTC)

Really really? Pure Iron and Pure Nickel dissolve in water containing no oxygen because their EMF is negative compared to hydrogen. Nickel silver (Nickel, Copper) often used in marine boilers react with Hydrazine. You would need some Hydrogen overpressure (100,000 psi?) to drive the reaction in reverse. Stainless alloys actuall rust faster than Iron in anoxic conditions. Chromate or other oxidizer used to be added to normal boilers to inhibit corrosion. Silicate and phosphate (used in car radiator fluid, too; anti freeze solution is a reducing e.m.f. organic) passivates surface oxide. Remember that rusting creates hydrogen which only leads to more rusting. Perhaps Nuclear boilers are not made from the same materials as coal-fired or nat gas fired power plants, fuel is encased in Zirconium, so this comment may not apply to exotic metals. Average person using the wiki will want it general or noted that it isn't.

Shjacks45 (talk) 20:49, 9 May 2010 (UTC)

Fuel Cell?[edit]

I thought Hydrogen electrode was 0.0 volts Shjacks45 (talk) 20:29, 9 May 2010 (UTC)


Hydrazine is said to resemble water. The article should say by how much it expands or contracts on freezing, preferably by giving the densities. (talk) 13:06, 10 May 2011 (UTC)


There seems to be no information in the article about it being a known carcinogenic and mutagenic inhibitor. (talk) 06:39, 17 July 2011 (UTC)

Hydrazine Hydrate[edit]

The most commonly sold hydrazine in chemical laboratory trade is a one-to-one molar hydrazine-water mixture. This mixture is partly ionized to hydrazinium hydroxide, though sans research I do not know the equilibrium constant. Because this item is an article of commerce, it deserves at least mention -- furtheremore, UH-25 rocket fuel uses UDMH with 25% hydrazine hydrate, and references hydrazine hydrate. Any opinions on whether or not hydrazine hydrate should be included in the main article on hydrazine or have its own separate article? Barring objections, I plan on including this section in the hydrazine article itself. Norm Reitzel (talk) 14:18, 14 February 2012 (UTC)

Fuel cell clarification[edit]

The Italian catalyst manufacturer Acta has proposed using hydrazine as an alternative to hydrogen in fuel cells. The chief benefit of using hydrazine is that it can produce over 200 mW/cm2 more than a similar hydrogen cell without the need to use expensive platinum catalysts

It would be useful to have this reworded or expanded with "x% more (energy) than a similar hydrogen cell". -- Katana (talk) 20:14, 19 June 2013 (UTC)


I was wondering, how flammable is hydrazine, and is it soluble in water? I wanted to make some with hydrogen peroxide and ammonia as one of my first real chemistry experiments. — Preceding unsigned comment added by (talk) 19:00, 12 November 2013 (UTC)

the next way under the synthesis and manufacture section[edit]

Hello. As no further information or sources had been provided in this article, the sentence has been hidden. Mountainninja (talk) 01:52, 6 May 2014 (UTC)

Ketazine process and other notes[edit]

The Ketazine process can be considered a middle ground between the Olin Raschig process and the Peroxide process.

1) Olin Raschig: chloramine or chlorine or hypochlorite oxidant on ammonia, no ketone 2) Ketazine: chloramine or chlorine or hypochlorite oxidant on ammonia, on ketone 3) Peroxide: hydrogen peroxide oxidant on ammonia, on ketone 4) oxidation on urea: hypochlorite oxidant on urea

The information on Ketazine process is unreferenced, so it cannot be added in the article content. Please help.

So in different perspectives, ketone or urea provides fixated amine or ammonia for chlorine or oxygen based oxidation; or imine or carbonyl fixates amine or ammonia for oxidation. I wonder if peroxide could act on urea. Then in scheme only, peroxide oxidizes carbonyl fixated amine group to yield carbon dioxide that can leave as gas. Liquid hydrazine remains in water. No ammonia is used so no ammonium salt (ammonium carbonate, for example).

-- Mountainninja (talk) 11:19, 8 February 2015 (UTC)

Thanks for the notice. I had redirected (Bayer) Ketazine Process to Peroxide Process, but you are correct - that was highly imperfect. Please continue to offer suggestions. I tried to patch things up: basically every permutation of NaOCl, ammonia, urea, and acetone has been developed, but it appears that Peroxide process is going to take over, although maybe not in countries with lax environmental regulations. It is an interesting idea that the urea route could be use peroxide. Someone must have thought of that variation. --Smokefoot (talk) 15:55, 8 February 2015 (UTC)
Thanks for the reply. I believe someone must have thought of that variation. What is interesting for all these permutations of ammonia oxidation is that virtually commonly used nitrogen based chemicals, such as hydroxylamine, which is used in making paracetamol, can be made from stepwise oxidation via these permutations.
ammonia NH3 ---> hydrazine N2H4 (or N2H6O minus H2O or NH3 minus half H2O) ---> hydroxylamine NH3O ---> nitroxyl/hyponitrous acid HNO/H2N2O2 (NH3O2 minus H2O) -- Mountainninja (talk) 23:12, 8 February 2015 (UTC)

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Lack of information[edit]

This article appears to be missing a lot of relevant information.

In many wiki pages referencing hydrazine and in other material on the internet, it is always mentioned how highly toxic this substance is both to humans and the environment in general. Yet this article has almost no information on this, there is a brief list of symptoms of hydrazine poisoning but no explanation of how and why this is such a toxic substance. What does it actually do when it is inside the body? How does this interact with non-human life such as plants, and what impact does it have on things like the water table?

Furthermore, there is a lack of information surrounding hydrazines use as a fuel additive in the earlier days of dragcar racing. I originally came to this page wanting to find out about this exceedingly unwise use of the chemical and the health risks associated with it after reading dozens of anecdotes about people mixing it with fuel.

This article is exceedingly narrow in scope and needs serious work. Taurich (talk) 03:09, 1 June 2016 (UTC)

Assessment comment[edit]

The comment(s) below were originally left at Talk:Hydrazine/Comments, and are posted here for posterity. Following several discussions in past years, these subpages are now deprecated. The comments may be irrelevant or outdated; if so, please feel free to remove this section.

Needs a good copy-edit before it is recommend for A-Class. 21:59, 17 February 2007 (UTC).

Last edited at 21:59, 17 February 2007 (UTC). Substituted at 18:34, 29 April 2016 (UTC)


the pka value in the table is on the right is wrong, its in fact the pka of the hydrazinium ion. i wouldve corrected it but couldnt find hydrazines pka anywhere. if anyone can find it, please add it. — Preceding unsigned comment added by (talk) 15:02, 30 June 2016 (UTC)