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Ammonia Synthesis - 0 views

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shared by Yeva Berkovich on 14 Feb 13 - No Cached
  • It has a sharp odor that stings the nostrils and it can cause suffocation if inhaled in sufficient quantity.
    • Yeva Berkovich
      Yeva Berkovich on 14 Feb 13
       
      neat
  • Although a practically inexhaustible source of nitrogen exists in the atmosphere, which consists of about 80 percent nitrogen, no one knew how to economically combine this with hydrogen to produce ammonia (NH3) on a large scale. In Germany, Fritz Haber began investigating this problem. In principle the chemistry of ammonia synthes
    • Yeva Berkovich
      Yeva Berkovich on 14 Feb 13
       
      materials available but process was unknown
  • The Haber-Bosch process has remained essentially unchanged since the early 1900s. It is used today to manufacture thousands of tons of ammonia worldwide, accounting for more than 85 percent of total ammonia production.
    • Yeva Berkovich
      Yeva Berkovich on 14 Feb 13
       
      what is the other 15% ?
19More

Gale Science In Context - Document - 2 views

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shared by Rajmund Niwinski on 14 Feb 13 - No Cached
  • iron-catalyzed Haber-Bosch process for ammonia synthesis
    • Rajmund Niwinski
      Rajmund Niwinski on 14 Feb 13
       
      The Haber process involves using overflow of reactants and removal of products to maximize ammonia production.
  • 150 to 550 atmospheres
    • Rajmund Niwinski
      Rajmund Niwinski on 14 Feb 13
       
      We learned that it was 200 atm. Which is it really?
  • high temperatures
    • Rajmund Niwinski
      Rajmund Niwinski on 14 Feb 13
       
      These are needed to keep a high forward reaction rate.
  • ...11 more annotations...
  • The metalloenzymes, called nitrogenases
    • Rajmund Niwinski
      Rajmund Niwinski on 14 Feb 13
       
      These act like the iron catalyst in the Haber process.
  • more energy-efficient process than Haber-Bosch
    • Rajmund Niwinski
      Rajmund Niwinski on 14 Feb 13
       
      Interesting: The same process has been used for almost a hundred years.
  • Perhaps a thousand man-years and billions of dollars have been spent studying how nitrogenases work and trying to make artificial ones
  • Perhaps a thousand man-years and billions of dollars have been spent studying how nitrogenases work and trying to make artificial ones.
  • Perhaps a thousand man-years and billions of dollars have been spent studying how nitrogenases work and trying to make artificial ones.
  • Perhaps a thousand man-years and billions of dollars have been spent studying how nitrogenases work and trying to make artificial ones.
  • Perhaps a thousand man-years and billions of dollars have been spent studying how nitrogenases work and trying to make artificial ones
  • Perhaps a thousand man-years and billions of dollars have been spent studying how nitrogenases work and trying to make artificial ones
  • Perhaps a thousand man-years and billions of dollars have been spent studying how nitrogenases work and trying to make artificial ones
  • Perhaps a thousand man-years and billions of dollars have been spent studying how nitrogenases work and trying to make artificial ones
  • Perhaps a thousand man-years and billions of dollars have been spent studying how nitrogenases work and trying to make artificial ones
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Gale Science In Context - Document - 1 views

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shared by Ngo Thien Quy on 14 Feb 13 - No Cached
  • A NEWLY invented metal compound can loosen the chemical bonds of the nitrogen molecules that make up four-fifths of the atmosphere
    • Ngo Thien Quy
      Ngo Thien Quy on 14 Feb 13
       
      In our atmosphere, the reactions between nitrogen and oxygen are in dynamic equilibrium where they continue to react. Surprisingly, nitrogen seems to be more abundant than oxygen is.
  • it must first be converted into ammonia (N[H.sub.3]), using an industrial process called Haber-Bosch, in which an iron catalyst is used to crack open the triple bond of the nitrogen molecule, at high temperature and pressure
    • Ngo Thien Quy
      Ngo Thien Quy on 14 Feb 13
       
      Nitrogen is basically unnecessary when it hasn't been broken down or reacted, becuase the nutrients from nitrogen are not able to be used.
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Gale Science In Context - Document - 0 views

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shared by Kaeley McGrane on 14 Feb 13 - No Cached
  • 2004
    • Kaeley McGrane
      Kaeley McGrane on 14 Feb 13
       
      What, if anything, has developed with this discovery since the publication of this article?
2More

Gale Science In Context - Document - 1 views

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shared by OB Rahim on 14 Feb 13 - No Cached
  • Carbon dioxide is the fourth most abundant gas in the atmosphere (after nitrogen, oxygen, and argon)
    • OB Rahim
      OB Rahim on 14 Feb 13
       
      What about Hydrogen?
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Ammonia transformed - 1 views

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shared by vinaireddy123 on 14 Feb 13 - No Cached
  • fertilizer made from this ammonia is estimated to be responsible for sustaining roughly 40% of the world's population and is the source for 40-60% of the nitrogen in the human body
    • faiyza osman
      faiyza osman on 14 Feb 13
       
      ammonia, as mentioned in the previous article, is cleary common in trying to maximize agricultural output....
  • As originally devised, the Haber-Bosch process involves the elements in their gaseous state interacting at high temperature and pressure over an activated iron surface.
  • Although predicted [4] a few years ago, this is the first observation of such a transformation. Why has it taken so long?
  • ...1 more annotation...
  • The answer is probably that molecular nitrogen is not that good a ligand.
  • vinaireddy123 on 14 Feb 13
     
    Vinai Reddy
76More

Gale Science In Context - Document - 14 views

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shared by Miral Tripathi on 14 Feb 13 - No Cached
  • Ammonia
    • Mrs. Byrge
      Mrs. Byrge on 14 Feb 13
       
      NH3
  • Ammonia is manufactured by the reaction of hydrogen with nitrogen in the presence of an iron catalyst, which is known as the Haber-Bosch process.
    • phillip an
      phillip an on 14 Feb 13
       
      Production of ammonia
  • Ammonia (boiling point -28.03°F [-33.35°C])
    • Vaibhav Tiwari
      Vaibhav Tiwari on 14 Feb 13
       
      This would mean that Ammonia is a gas at room temperature.
  • ...34 more annotations...
  • In ancient Egypt, ammonium compounds were used in rites honoring the god Ammon, from which came the name we still use for the gas and its compounds.
    • Alicia Stephen
      Alicia Stephen on 14 Feb 13
       
      Interesting origins of Ammonia and its name...
  • ammonia was sometimes manufactured by the action of steam on calcium cyanamide, called the cyanamide process, which in turn was made by reacting calcium carbide with nitrogen at high temperatures.
    • vivek shankar
      vivek shankar on 14 Feb 13
       
      What is the chemical reaction for the cyanamide process?
    • phillip an
      phillip an on 14 Feb 13
       
      CaC2 + N2 → CaCN2 + C
    • phillip an
      phillip an on 14 Feb 13
       
      Further produced calcium cyanamide gives together with water steam calcium carbonate and ammonia: CaCN2 + 3 H2O → CaCO3 + 2 NH3
  • Joseph Priestley (1733-1804) first collected and experimented with the pure substance. C. L. Berthollet (1748-1822) proved that ammonia is composed of nitrogen and hydrogen.
    • Alicia Stephen
      Alicia Stephen on 14 Feb 13
       
      Very important that this discovery was made-- otherwise there would be no deerhorn left..
  • The largest use of ammonia is in fertilizers, which are applied to the soil and help provide increased yields of crops such as corn, wheat, and soybeans. Liquid ammonia, ammonia/water solutions, and chemicals made from ammonia, such as ammonium salts and urea, are all used as sources of soluble nitrogen. Urea, which is made from ammonia and carbon dioxide, can also be used as a feed supplement for cattle, aiding in the rapid building of protein by the animals.
    • phillip an
      phillip an on 14 Feb 13
       
      Ammonia is used in many facets of daily life
  • by high-pressure catalytic reactions of nitrogen (from air) with hydrogen.
    • Alexa Wisniarek
      Alexa Wisniarek on 14 Feb 13
       
      Using pressure to shift the equilibrium.
    • Miral Tripathi
      Miral Tripathi on 14 Feb 13
       
      Talks about pressure but not about tempurature.
  • The copper (II) ammonia complex, in solution, is deep blue in color,
    • Vaibhav Tiwari
      Vaibhav Tiwari on 14 Feb 13
       
      We learned this in periodicty, the colors of the transition metals, and copper is blue.
  • German chemists Fritz Haber and Carl Bosch learned how to make ammonia in large quantities by high-pressure catalytic reactions of nitrogen (from air) with hydrogen.
  • The Haber-Bosch process is the basis for modern ammonia production, although many improvements have been made in the details of the technology.
    • Alicia Stephen
      Alicia Stephen on 14 Feb 13
       
      How ammonia is produced
  • be made in the laboratory by heating ammonium chloride with lime, and the gas collected by downward displacement of air, or displacement of mercury.
    • Miral Tripathi
      Miral Tripathi on 14 Feb 13
       
      The actual process of making ammonia
  • a weak base, turning litmus paper blue, and neutralizing acids with the formation of ammonium salts.
    • Alicia Stephen
      Alicia Stephen on 14 Feb 13
       
      Characteristics of Ammonia..
    • vivek shankar
      vivek shankar on 14 Feb 13
       
      Litmus test gives an indication of how acidic a substance is; the color the Litmus paper turns is related to a specific pH value
  • Ammonium nitrate is used as a high explosive; ammonium perchlorate is a component of rocket fuels.
    • Alexa Wisniarek
      Alexa Wisniarek on 14 Feb 13
       
      It's used for both "good purposes", like fertilizer, and "bad" purposes, like weapons.
  • ability to dissolve cellulose, and has been used in the process for making regenerated cellulose fibers, or rayon.
    • Alicia Stephen
      Alicia Stephen on 14 Feb 13
       
      This is really interesting... guess that explains why we can't digest cellulose...
  • Ammonia molecules possess a pyramidal shape, with the nitrogen atom at the vertex.
  • Ammonia molecules possess a pyramidal shape, with the nitrogen atom at the vertex.
    • Alicia Stephen
      Alicia Stephen on 14 Feb 13
       
      Shapes of molecules.. we learned this sophomore chem (VSEPR)
  • (The ammonia occupies less volume than the gases from which it is made.) High pressure conditions (150-250 bar) are used, and temperatures range from 752-932°F (400-500°C). The mixed gases circulate through the catalyst, ammonia is formed and removed, and the unconverted reactants are recirculated.
    • Alexa Wisniarek
      Alexa Wisniarek on 14 Feb 13
       
      High pressure. High temperature, even though there would be more Ammonia production at low temeperature, to speed up the rate of reaction.
  • Nitrogen fixation
    • Vaibhav Tiwari
      Vaibhav Tiwari on 14 Feb 13
       
      Will we learn about Nitrogen Fixation in chem, or is it in bio, or neither or them?
    • phillip an
      phillip an on 14 Feb 13
       
      Nitrogen fixation is a process by which nitrogen in the atmosphere is converted into ammonia, so i would think we would learn about it in chem
  • Ammonium salts such as ammonium chloride, called sal ammoniac, are water soluble and volatile when heated.
    • Alicia Stephen
      Alicia Stephen on 14 Feb 13
       
      What are the salts used for?
  • The gases that enter the catalytic converter must be highly purified and free of sulfur compounds, which adversely affect the catalyst.
    • Alexa Wisniarek
      Alexa Wisniarek on 14 Feb 13
       
      Interesting that sulfur adversely affects the catalyst.
  • Nitric acid and nitrates are needed for the manufacture of explosives like TNT, nitroglycerin, gunpowder, and also for the propellants in cartridges for rifles and machine guns.
    • Vaibhav Tiwari
      Vaibhav Tiwari on 14 Feb 13
       
      If all other important nitrogen chemicals are now made from ammonia, wouldn't that cause a shortage in Ammonia? Earlier in the reading it said that the production of Ammonia did not meet its demands and it had to be imported, if we stopped making it for Nitric acid and other nitrates that are used for explosives, we wouldn't have such a shortage.
  • When ammonium hydroxide is treated with iodine crystals, an explosive brown solid, nitrogen triiodide, is formed.
    • james huang
      james huang on 14 Feb 13
       
      Example of chemical reaction with the use of ammonia.
  • Two types of polymers needed for artificial fibers require the use of ammonia, polyamides (nylon), and acrylics (orlon).
  • where it may have originally formed from metal nitrides reacting with water.
    • james huang
      james huang on 14 Feb 13
       
      How do we know the origins of why liquid and solid ammonia exist on other planets? Where is the proof regarding this theory?
  • Since the hydrogen is usually derived from a natural gas called methane, the price of ammonia is very sensitive to the availability or price of fuels.
    • Alicia Stephen
      Alicia Stephen on 14 Feb 13
       
      Not the easiest thing to predict.. not much stability
  • These bacteria and algae possess an enzyme called nitrogenase that permits them to convert nitrogen to ammonia at 77°F (25°C) and 1 bar of pressure, much milder conditions than those of the Haber-Bosch process.
    • Alexa Wisniarek
      Alexa Wisniarek on 14 Feb 13
       
      Really interesting and neat that they can do that.
  • Ammonia will continue to be important for agriculture and for the whole nitrogen chemicals industry.
    • james huang
      james huang on 14 Feb 13
       
      Ammonia and its impact in the future. Ammonia has served many purpose in the past, present and in the years to come.
  • blue-green algae in the sea.
    • Alicia Stephen
      Alicia Stephen on 14 Feb 13
       
      So can it form in the sea, or no?
  • Ammonia has also been detected in interstellar space by radioastronomy.
    • phillip an
      phillip an on 14 Feb 13
       
      Is ammonia correlated with the origin of life?
  • ammonia is able to react with acidic gases such as nitrogen oxides and sulfur oxides to form ammonium salts
    • james huang
      james huang on 14 Feb 13
       
      What basic properties allow Ammonia to react with acidic gases and form salts?
  • planets
  • In liquid or frozen ammonia, the molecules attract one another through sharing a hydrogen atom between one molecule and the next, called hydrogen bonding. In this attraction, called association, compounds apparently containing free electrons can be obtained by treating sodium/ammonia solutions with complexing agents.
    • Miral Tripathi
      Miral Tripathi on 14 Feb 13
       
      Properties of bonding
  • Ammonia has also been detected in interstellar space by radioastronomy.
    • Alicia Stephen
      Alicia Stephen on 14 Feb 13
       
      Interesting.. can we ever get to a point where we can get ammonia from "interstellar space"?
  • , as the nations evolve toward alternative fuels.
    • Alexa Wisniarek
      Alexa Wisniarek on 14 Feb 13
       
      Will Ammonia change the transportation of the future?
  • Asia and Latin America develop higher standards of living and stronger economies, they will need their own ammonia plants.
    • Alicia Stephen
      Alicia Stephen on 14 Feb 13
       
      This is pretty important for powerful countries
  • Ammonia is a flammable gas and reacts with oxygen to form nitrogen and water, or nitrogen (II) oxide and water.
    • Miral Tripathi
      Miral Tripathi on 14 Feb 13
       
      Ammonia is combustable
  • Mrs. Byrge on 14 Feb 13
     
    B3 Annotation
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Gale Science In Context - Document - 2 views

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shared by Shirley Lu on 14 Feb 13 - No Cached
  • are water soluble and volatile when heated.
  • Ammonia is a flammable gas and reacts with oxygen to form nitrogen and water, or nitrogen (II) oxide and water.
    • Saad Shaik
      Saad Shaik on 14 Feb 13
       
      Properties of Ammonia
  • High pressure conditions (150-250 bar) are used, and temperatures range from 752-932°F (400-500°C).
    • Saad Shaik
      Saad Shaik on 14 Feb 13
       
      Shifts Equilibrium so more Ammonia is made
    • Amy Chern
      Amy Chern on 14 Feb 13
       
      Reactants are reused to make proccess more efficient
  • ...34 more annotations...
  • boiling point -28.03°F [-33.35°C]
    • Shirley Lu
      Shirley Lu on 14 Feb 13
       
      gas at room temperature
  • high-pressure catalytic reactions of nitrogen (from air) with hydrogen
    • Yeva Berkovich
      Yeva Berkovich on 14 Feb 13
       
      high pressure because it pushes the forward reaction
    • Amy Chern
      Amy Chern on 14 Feb 13
       
      shift equilibrium as far to the right as possible to increase yield and to speed up production rate- high pressure and catalyst
  • The largest use of ammonia is in fertilizers,
    • Saad Shaik
      Saad Shaik on 14 Feb 13
       
      this is why ammonia is so important
  • may have been the source of nitrogen for the earliest forms of life, although much controversy exists over the details
    • Nina Chen
      Nina Chen on 14 Feb 13
       
      It is still debated whether or not the early life forms used nitrogen. Not enough evidence may be known.
  • German chemists Fritz Haber and Carl Bosch learned how to make ammonia in large quantities by high-pressure catalytic reactions of nitrogen (from air) with hydrogen.
    • Amy Chern
      Amy Chern on 14 Feb 13
       
      Shift equilibrium as far to the right as possible to increase yield and to speed up production - high pressure and catalyst
  • In ancient Egypt, ammonium compounds were used in rites honoring the god Ammon, from which came the name we still use for the gas and its compounds.
    • Joshua Yohannan
      Joshua Yohannan on 14 Feb 13
       
      this is important because a lot of things originated in ancient egypt
  • Ammonia, composed of three parts hydrogen and one part nitrogen, is a sharp-smelling, flammable, and toxic gas that is very soluble in water, where it acts as a base in its chemical reactions.
    • Saad Shaik
      Saad Shaik on 14 Feb 13
       
      Basic definition and properties of Ammonia
    • Joshua Yohannan
      Joshua Yohannan on 14 Feb 13
       
      this is basically what ammonia is.
  • In this attraction, called association,
    • Yeva Berkovich
      Yeva Berkovich on 14 Feb 13
       
      is it always called attraction, or is that just for this molecule?
  • ammonia was sometimes manufactured by the action of steam on calcium cyanamide, called the cyanamide process,
    • Vickie Xin
      Vickie Xin on 14 Feb 13
       
      Previous process of making ammonia - cyanamide process
  • German chemists Fritz Haber and Carl Bosch
    • Joshua Yohannan
      Joshua Yohannan on 14 Feb 13
       
      eventually they competed against each other because they both wanted to know about ammonia
  • such as Jupiter, where it may have originally formed from metal nitrides reacting with water.
    • james huang
      james huang on 14 Feb 13
       
      How do we know where liquid and solid ammonia have have formed? Do we know that these theories are correct?
  • The mixed gases circulate through the catalyst, ammonia is formed and removed, and the unconverted reactants are recirculated.
  • ammonia is able to react with acidic gases such as nitrogen oxides and sulfur oxides to form ammonium salts
    • james huang
      james huang on 14 Feb 13
       
      Ammonia's special chemical properties allow it to react with acidic gases to form salts.
  • Ammonia is formed from nitrogen in air by the action of nitrogen-fixing bacteria that exist in the soil on the roots of certain plants like alfalfa.
    • Joshua Yohannan
      Joshua Yohannan on 14 Feb 13
       
      is this the haber process?
  • The synthesis reaction itself produces some heat, and great attention is given to heat efficiency and use of waste heat.
    • Saad Shaik
      Saad Shaik on 14 Feb 13
       
      Being as efficient as possible
    • Shirley Lu
      Shirley Lu on 14 Feb 13
       
      exothermic reaction -- but the rate of the reaction must also be taken into account --> balance between increasing yield (application of Le Chatelier's) and producing the ammonia at an efficient rate
  • which amounts to about 40 pounds (18 kg) for each person on Earth.
    • Joshua Yohannan
      Joshua Yohannan on 14 Feb 13
       
      it's surprising how much of an impact the haber process made in the world
  • Ammonium hydroxide exhibits the characteristics of a weak base,
    • Vickie Xin
      Vickie Xin on 14 Feb 13
       
      water solution of ammonia is a weak base
  • Much nitrogen is normally excreted by humans (and other mammals) as urea, a water soluble solid, but fish can excrete ammonia directly.
    • Yeva Berkovich
      Yeva Berkovich on 14 Feb 13
       
      fish are cool
  • These bacteria and algae possess an enzyme called nitrogenase that permits them to convert nitrogen to ammonia at 77°F (25°C) and 1 bar of pressure, much milder conditions than those of the Haber-Bosch process.
    • Saad Shaik
      Saad Shaik on 14 Feb 13
       
      Process can happen naturally
  • Although Earth's atmosphere is free of ammonia
    • Joshua Yohannan
      Joshua Yohannan on 14 Feb 13
       
      this is surprising because there is ammonia in other atmospheres of other planets
  • feed supplement for cattle, aiding in the rapid building of protein by the animals.
    • Yeva Berkovich
      Yeva Berkovich on 14 Feb 13
       
      is this good for the well being of cows?
  • presence of an iron catalyst
    • Nina Chen
      Nina Chen on 14 Feb 13
       
      Speeds up the reaction but doesn't change the equilibrium point
  • nited
  • United States production of ammonia reached 17 million tons in 1991, and demand was even larger than U.S. production, leading to about two million tons of imports.
    • Amy Chern
      Amy Chern on 14 Feb 13
       
      Haber Process is important because ammonia is in high demand - need to have the most efficient and economical process for producing ammonia
  • the lightest touch will cause it to explode with a crackling sound and a puff of purple iodine vapor.
    • Joshua Yohannan
      Joshua Yohannan on 14 Feb 13
       
      so creating ammonia through the haber process can be dangerous if not handled with extreme care. should we create as much ammonia as we do?
  • corrosive and volatile ingredient in fuels.
    • Vickie Xin
      Vickie Xin on 14 Feb 13
       
      Ammonia is commonly used in fuels and explosives
  • When dry, this substance is so sensitive that the lightest touch will cause it to explode with a crackling sound and a puff of purple iodine vapor.
    • vinaireddy123
      vinaireddy123 on 14 Feb 13
       
      Interesting...
  • strong color
    • Nina Chen
      Nina Chen on 14 Feb 13
       
      What makes a color 'strong'?
  • New uses may develop, particularly for ammonia as a relatively inexpensive base with unique properties, for liquid ammonia as a solvent, and as a storage medium for hydrogen, as the nations evolve toward alternative fuels.
    • Amy Chern
      Amy Chern on 14 Feb 13
       
      New uses of Ammonia are continously being discovered
  • For this reason, capacity and production will continue to grow
    • Joshua Yohannan
      Joshua Yohannan on 14 Feb 13
       
      creation of ammonia will always be important because it helps so much with agriculture and other things.
  • Ammonia can be formed in the human body and may build up abnormally during serious illnesses such as Reye's syndrome.
    • vinaireddy123
      vinaireddy123 on 14 Feb 13
       
      What causes this build up of ammonia?
  • New uses may develop, particularly for ammonia as a relatively inexpensive base with unique properties, for liquid ammonia as a solvent, and as a storage medium for hydrogen, as the nations evolve toward alternative fuels.
    • Saad Shaik
      Saad Shaik on 14 Feb 13
       
      unless they find something better
  • 200,000 tons of ammonia were released into the environment
    • Shirley Lu
      Shirley Lu on 14 Feb 13
       
      negative environmental impact
  • earned to generate ammonia from animal parts such as deerhorn, and obtained ammonial preparations
    • Amy Chern
      Amy Chern on 14 Feb 13
       
      Ammonia has long been used for various purposes.
32More

Case Study: The Haber Process - ChemWiki - 3 views

chemwiki.ucdavis.edu/...Haber_Process
shared by Amy Chern on 14 Feb 13 - No Cached
  • commercial synthesis of ammonia
    • Shirley Lu
      Shirley Lu on 14 Feb 13
       
      production of ammonia with maximum efficiency
  • conditions for the formation of ammonia
    • Shirley Lu
      Shirley Lu on 14 Feb 13
       
      conditions for highest yield
    • Amy Chern
      Amy Chern on 14 Feb 13
       
      This would include pressure, and increasing reactants
  • work of high-pressure on chemical reactions (developed into industrial process)
    • Shirley Lu
      Shirley Lu on 14 Feb 13
       
      effects of pressure -- increased pressure --> increased yield
  • ...13 more annotations...
  • During the 1920’s, there was a shortage of the world's supply for fixed nitrogen.
    • Shirley Lu
      Shirley Lu on 14 Feb 13
       
      historical background -- was in high demand
  • mainly used for fertilizer
    • Shirley Lu
      Shirley Lu on 14 Feb 13
       
      fertilizer --> agricultural importance -- crucial to maintain food supply (especially during wartime)
  • N2(g) + 3H2(g) → 2NH3(g)     ΔH=-92.4 kJ
    • Shirley Lu
      Shirley Lu on 14 Feb 13
       
      forward, exothermic reaction; all reactants and products are in gas state
  • 2NH3(g) → N2(g) + 3H2(g)     ΔH=+ 92.4 kJ mol-1
    • Shirley Lu
      Shirley Lu on 14 Feb 13
       
      reverse, endothermic reaction
  • takes place under high pressure and temperature and with an iron catalyst***
    • Shirley Lu
      Shirley Lu on 14 Feb 13
       
      shifts equilibrium to right, pushing forward reaction to maximize yield of ammonia
  • Chemical equilibrium is when a reaction has no tendency to change the quantity of the products and reactants, so the reaction can go both ways.
    • Miral Tripathi
      Miral Tripathi on 14 Feb 13
       
      Definition of chemical equilibrium
  • A catalyst is used to speed up a reaction by lowering the activation energy. So, in this reaction, the iron catalyst is used to lower the activation energy so that the N2 and H2 can be easier to break down.
    • Miral Tripathi
      Miral Tripathi on 14 Feb 13
       
      Less energy is needed but the yeild is still the same
  • used in order to produce food, so that in WWI people could continue to fight. It only requires 1 percent of the world's energy to make 500 million tons of artificial fertilizer per year, which, in turn, helps feed 40 percent of the world's population.
    • Amy Chern
      Amy Chern on 14 Feb 13
       
      Origins of the Haber process - needed during World War I. Ammonia for use in fertilizer is effective and economical
  • exothermic reaction,
    • Amy Chern
      Amy Chern on 14 Feb 13
       
      Equilibrium - desirable to have lower temperature to shift equilibrium to the right Kinetics - higher temperature would result in faster reaction Must reach a compromise between the two.
    • Shirley Lu
      Shirley Lu on 14 Feb 13
       
      enthalpy diagram -- catalysed has lower activation energy
    • Shirley Lu
      Shirley Lu on 14 Feb 13
       
      applications of Le Chatelier's Principle
  • When you increase the pressure so that the least amount of molecules will be formed, there won't be an increase in collisions. However, if more gas molecules are formed, there will be an increase in collisions, thus moving the way that will produce the least amount of molecules.
    • Shirley Lu
      Shirley Lu on 14 Feb 13
       
      explanation using collision theory
  • German Chemists
    • Vickie Xin
      Vickie Xin on 14 Feb 13
       
      Germany was in fear of war with England. The knew that if they were to go to war with England, their imports would be halted. These imports were needed to create ammonia. Haber and Bosch were able to find a new way to create ammonia without those imports.
  • Shirley Lu on 14 Feb 13
     
    Shirley Lu
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