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Wife committed suicideafter first gas attack performed by Fritz, son travelled to America and comitted suicide

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The exposure to a low concentration of poisionous gas for a long time often has the same effect (death) as exposure to a higher concentration for a short time. He formulated a simple mathematical relationship between the gas concentration and the exposure time. Zis relationzip became known az Haber's rule.

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Haber played a major role in the development of chemical warfare in World War I. Part of this work included the development of gas masks with absorbent filters. Haber received much criticism for his involvement in the development of chemical weapons in pre-World War II Germany both by contemporaries and by modern-day scientists.

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Haber played a major role in the development of chemical warfare in World War I. Part of this work included the development of gas masks with absorbent filters. Haber received much criticism for his involvement in the development of chemical weapons in pre-World War II Germany both by contemporaries and by modern-day scientists.

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Next, he was villain, at least to non-Germans: Haber was the driving force 
behind Germany's use of chemical weapons in World War I, personally supervising 
the development and release of deadly chlorine, phosgene, and mustard. Even 
Haber's great nitrogen-fixing invention was first employed not to produce food 
but to provide explosives for war. Without Haber's invention, Germany would have 
been forced to capitulate within a year after the war began.

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Next, he was villain, at least to non-Germans: Haber was the driving force 
behind Germany's use of chemical weapons in World War I, personally supervising 
the development and release of deadly chlorine, phosgene, and mustard. Even 
Haber's great nitrogen-fixing invention was first employed not to produce food 
but to provide explosives for war. Without Haber's invention, Germany would have 
been forced to capitulate within a year after the war began.

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An astonishing fact: Half of all the nitrogen molecules within our bodies have 
come from a factory using Haber's process. This invention is what earned him the 
Nobel prize for chemistry.

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An astonishing fact: Half of all the nitrogen molecules within our bodies have 
come from a factory using Haber's process. This invention is what earned him the 
Nobel prize for chemistry.

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The Haber Process combines nitrogen from the air with hydrogen derived mainly from natural gas (methane) into ammonia. The reaction is reversible and the production of ammonia is exothermic.
The proportions of nitrogen and hydrogen
The mixture of nitrogen and hydrogen going into the reactor is in the ratio of 1 volume of nitrogen to 3 volumes of hydrogen.

Avogadro's Law says that equal volumes of gases at the same temperature and pressure contain equal numbers of molecules. That means that the gases are going into the reactor in the ratio of 1 molecule of nitrogen to 3 of hydrogen.

That is the proportion demanded by the equation.

In some reactions you might choose to use an excess of one of the reactants. You would do this if it is particularly important to use up as much as possible of the other reactant - if, for example, it was much more expensive. That doesn't apply in this case.

There is always a down-side to using anything other than the equation proportions. If you have an excess of one reactant there will be molecules passing through the reactor which can't possibly react because there isn't anything for them to react with. This wastes reactor space - particularly space on the surface of the catalyst.
The temperature Equilibrium considerations
You need to shift the position of the equilibrium as far as possible to the right in order to produce the maximum possible amount of ammonia in the equilibrium mixture.

The forward reaction (the production of ammonia) is exothermic.

According to Le Chatelier's Principle, this will be favoured if you lower the temperature. The system will respond by moving the position of equilibrium to counteract this - in other words by producing more heat.
Rate considerations
In order to get as much ammonia as possible in the equilibrium mixture, you need as low a temperature as possible. However, 400 - 450°C isn't a low temperature!

The lower the temperature you use, the slower the reaction becomes. A manufacturer is trying to produce as much ammonia as possible per day. It makes no sense to try to achieve an equilibrium mixture which contains a very high proportion of ammonia if it takes several years for the reaction to reach that equilibrium.
The compromise
You need the gases to reach equilibrium within the very short time that they will be in contact with the catalyst in the reactor.
The pressure Equilibrium considerations
400 - 450°C is a compromise temperature producing a reasonably high proportion of ammonia in the equilibrium mixture (even if it is only 15%), but in a very short time.

Notice that there are 4 molecules on the left-hand side of the equation, but only 2 on the right.
Rate considerations
According to Le Chatelier's Principle, if you increase the pressure the system will respond by favouring the reaction which produces fewer molecules. That will cause the pressure to fall again.
Economic considerations
In order to get as much ammonia as possible in the equilibrium mixture, you need as high a pressure as possible. 200 atmospheres is a high pressure, but not amazingly high.

Increasing the pressure brings the molecules closer together. In this particular instance, it will increase their chances of hitting and sticking to the surface of the catalyst where they can react. The higher the pressure the better in terms of the rate of a gas reaction.

Very high pressures are very expensive to produce on two counts.
The compromise
You have to build extremely strong pipes and containment vessels to withstand the very high pressure. That increases your capital costs when the plant is built.
The catalyst Equilibrium considerations
High pressures cost a lot to produce and maintain. That means that the running costs of your plant are very high.
Rate considerations
200 atmospheres is a compromise pressure chosen on economic grounds. If the pressure used is too high, the cost of generating it exceeds the price you can get for the extra ammonia produced.
Separating the ammonia
The catalyst has no effect whatsoever on the position of the equilibrium. Adding a catalyst doesn't produce any greater percentage of ammonia in the equilibrium mixture. Its only function is to speed up the reaction.

In the absence of a catalyst the reaction is so slow that virtually no reaction happens in any sensible time. The catalyst ensures that the reaction is fast enough for a dynamic equilibrium to be set up within the very short time that the gases are actually in the reactor.

When the gases leave the reactor they are hot and at a very high pressure. Ammonia is easily liquefied under pressure as long as it isn't too hot, and so the temperature of the mixture is lowered enough for the ammonia to turn to a liquid. The nitrogen and hydrogen remain as gases even under these high pressures, and can be recycled.
Some notes on the conditions The catalyst
A flow scheme for the Haber Process looks like this:
The pressure
The catalyst is actually slightly more complicated than pure iron. It has potassium hydroxide added to it as a promoter - a substance that increases its efficiency.
Recycling
The pressure varies from one manufacturing plant to another, but is always high. You can't go far wrong in an exam quoting 200 atmospheres.

At each pass of the gases through the reactor, only about 15% of the nitrogen and hydrogen converts to ammonia. (This figure also varies from plant to plant.) By continual recycling of the unreacted nitrogen and hydrogen, the overall conversion is about 98%.

© Jim Clark 2002 (modified April 2013)

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The Haber Process for the manufacture of ammonia

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The Haber Process combines nitrogen from the air with hydrogen derived mainly from natural gas (methane) into ammonia. The reaction is reversible and the production of ammonia is exothermic. The proportions of nitrogen and hydrogen The mixture of nitrogen and hydrogen going into the reactor is in the ratio of 1 volume of nitrogen to 3 volumes of hydrogen.

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a new Nazi-appointed director of the institute was likely „to study chemical warfare with the Institute…. You will remember that in was time I have been the leader of the chemical warfare in Germany and that I have been proud to work for the military authorities with the institute as an experimental basis. But after the Armistice, I have cancelled every such work and fully declined to renew it in whatever form.‟

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a new Nazi-appointed director of the institute was likely „to study chemical warfare with the Institute…. You will remember that in was time I have been the leader of the chemical warfare in Germany and that I have been proud to work for the military authorities with the institute as an experimental basis. But after the Armistice, I have cancelled every such work and fully declined to renew it in whatever form.‟

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Having once worked tirelessly as an advocate of the German nation, continuously trying to strengthen her both her internal and international standings, to now be singled-out and regarded as nothing more than a Jew must have broken Haber‟s heart. - 55 - 
Although he had been labeled as Jewish, Haber did have to option of remaining in his office, because he was a veteran of war. This option was at first considered a great deal by Haber, because if he remained in his position, from there he could aid those younger Jewish scientists who now found themselves in a bad predicament.

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Having once worked tirelessly as an advocate of the German nation, continuously trying to strengthen her both her internal and international standings, to now be singled-out and regarded as nothing more than a Jew must have broken Haber‟s heart. - 55 - 
Although he had been labeled as Jewish, Haber did have to option of remaining in his office, because he was a veteran of war. This option was at first considered a great deal by Haber, because if he remained in his position, from there he could aid those younger Jewish scientists who now found themselves in a bad predicament.

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Hitler‟s rise to power seems to correlate with Haber‟s own demise. In a letter to his son, Haber stated, bitterly, that Hitler‟s National Social Party had gained "a few millions" in campaign funding. So when, in the 1932 election, the Nazis became the single largest party in Germany, Haber must have felt some sense of an impending crisis. The Nazi party had already been affecting Haber‟s life for some time. For the last few months, he would have been a witness to the increased hostility amongst those around him. In fact, employees who were National Socialists had begun throwing accusations at their co-workers, accusing them of communist activities. Yet even with all this going on, it is doubtful that Haber fully understood how far and how fast the Nazi‟s would turn against those of Jewish heritage. 

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Hitler‟s rise to power seems to correlate with Haber‟s own demise. In a letter to his son, Haber stated, bitterly, that Hitler‟s National Social Party had gained "a few millions" in campaign funding. So when, in the 1932 election, the Nazis became the single largest party in Germany, Haber must have felt some sense of an impending crisis. The Nazi party had already been affecting Haber‟s life for some time. For the last few months, he would have been a witness to the increased hostility amongst those around him. In fact, employees who were National Socialists had begun throwing accusations at their co-workers, accusing them of communist activities. Yet even with all this going on, it is doubtful that Haber fully understood how far and how fast the Nazi‟s would turn against those of Jewish heritage. 

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By 1926, Fritz Haber‟s health was rapidly deteriorating. Having given up his work dealing with chemical weaponry research and manufacturing, he turned his attention to "more general scientific themes".2 Although he could no longer spend all his energy at the institute, for he had accepted a variety of public responsibilities, he was a large part in the bringing about of a sort of golden age at the institute. 

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By 1926, Fritz Haber‟s health was rapidly deteriorating. Having given up his work dealing with chemical weaponry research and manufacturing, he turned his attention to "more general scientific themes".2 Although he could no longer spend all his energy at the institute, for he had accepted a variety of public responsibilities, he was a large part in the bringing about of a sort of golden age at the institute. 

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Albert Einstein called Haber's life "the tragedy of the German Jew: the tragedy 
of unrequited love."

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Albert Einstein called Haber's life "the tragedy of the German Jew: the tragedy 
of unrequited love."

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The nytheater indie theater archive is the history of an artistic community. Its preservation is essential, as a monument to the great work that it encompassed and as a guidepost and inspiration to future generations of theater-makers.

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It has been claimed that as many as two out of five humans on the planet today owe their existence to the discoveries made by one brilliant German chemist.

Yet this is the same chemist denounced by young German students today as a "murderer".

No-one personifies better than Fritz Haber the debate over science's capacity for good and evil.

And there is more to his dramatic life even than this. For Haber personifies too the tragedy of a Jew desperate to be a patriotic German, whose life was destroyed after the Nazis came to power.

And in the cruellest of all the ironies, his work was developed under the Nazis to create the gas used to murder millions in the Holocaust - including his relatives.

Fritz Haber was born in 1868 in Breslau, in what is now Poland.

As a young man he was bursting with ambition. "We only want one limit, the limit of our own ability," he wrote.

He went to study chemistry in Berlin - the ideal formula, he hoped, for transforming a provincial Jewish boy into a successful German.

Historian Fritz Stern, whose parents were close friends of Haber, says he was "ambitious but also vulnerable".

It was an exhilarating time, as Germany, newly unified under the Kaiser, powered ahead with scientific research at the forefront.

But anti-Semitism also grew as the century drew to a close, which preyed on Haber's mind despite his decision to convert to Christianity.

'Bread from air'

The breakthrough that made his name answered one of the great challenges of the time - feeding growing populations.

Crops needed better supplies of nitrogen to produce more food. Previously this had been supplied in a limited and laborious way by ships full of bird droppings or nitrates mined in South America.

But in 1909 Haber found a way of synthesising ammonia for fertiliser from nitrogen and hydrogen.

Working with Carl Bosch, an engineer from the chemical company BASF, the Haber-Bosch process was born, making it possible to create huge amounts of fertiliser.

It seemed miraculous, described as creating "bread from air".

The fertiliser went on to be used on a large scale, bringing about a huge increase in crop yields, and practically banishing the fear of famine in large parts of the world.

One observer describes it as "the most important technological invention of the 20th Century".

Poison gas

But the process was also highly useful for the military in making explosives.

And when World War I broke out soon afterwards, Haber - now working for the Kaiser's research institute in Berlin - was desperate to prove his patriotism.

He began experimenting with chlorine gas which, he said, would shorten the war.

The first attack using his methods was at Ypres in 1915. Haber was promoted to captain in the German army - but on the night he celebrated promotion in his villa in Berlin, his wife committed suicide.

Clara Immerwahr, a trained chemist, had become increasingly frustrated with her life at home looking after their son, and with the military direction of her husband's research.

Haber rushed back to the front, apparently unmoved. But in a letter soon afterwards he wrote: "I hear in my heart the words that the poor woman once said... I see her head emerging from between orders and telegrams, and I suffer."

By the end of the war he had re-married, but his reputation was as uncertain as ever. Awarded the Nobel Prize for his work on ammonia, he also feared arrest as a war criminal for his poison gas research.

In the new Germany of the Weimar Republic, Haber continued to strive patriotically, with characteristic self-confidence.

The country faced huge reparations payments. Haber claimed he could extract gold from seawater to pay off the debts - but this time there was no miraculous breakthrough.

'Jews not allowed'

By the early 1930s he could see vicious anti-Semitism spreading around him, and his claim to be a German patriot was no protection.

"In early 1933", his daughter Eva told me, "he went to his institute. There was the porter, who said: 'The Jew Haber is not allowed in here.'"

Haber resigned, devastated, went briefly into exile, and died of a heart attack in 1934.

Despite the significance of his discoveries he remains much less well known than his friend and colleague Albert Einstein - perhaps because his reputation is so disputed.

It was not just the poison gas. There was one other area of research in the 1920s in which Haber and his colleagues were successful: developing pesticide gases.

Of Haber's legacies, this was the bitterest. For this research was later developed into the Zyklon process, used by the Nazis to murder millions in their death camps, including his own extended family.

His godson, historian Fritz Stern, says we must remember Haber "in all his complexity". He was a man of "scientific greatness, deeply cultivated".

But in an "excess of patriotism" he invented gas warfare, which "has come to define... the unspeakable horror of the First World War".

And as for his tortured relationship with Germany, Einstein concluded: "Haber's life was the tragedy of the German Jew - the tragedy of unrequited love."

You can hear Chris Bowlby's The Chemist of Life and Death on BBC Radio 4 on Tuesday 12 April at 2100 BST and again on Wednesday 13 April at 1630. You can also listen on the iPlayer .

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Fritz Haber: Jewish chemist whose work led to Zyklon B

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It has been claimed that as many as two out of five humans on the planet today owe their existence to the discoveries made by one brilliant German chemist. Yet this is the same chemist denounced by young German students today as a "murderer".