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  Periodic Table  Haber Process Steps
  Rejected Periodic Table Kangen Water


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 History

 Uses and Raw Materials

 Reversible Reactions

 Le Chatelier's Principle

 Industrial Conditions

 Fertilizers



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History

 The Haber Process is a method of producing ammonia developed in WWI.  The Germans needed nitrogen to for making their explosives.  When the Allies blocked off all trade routes going to and from Germany, they lost all source of sodium nitrate and potassium nitrate, their source of nitrogen.  They found their source of nitrogen in the air, which was 80% nitrogen. The chemist Fritz Haber developed the Haber Process in WWI, which takes molecular nitrogen from the air and combines it with molecular hydrogen to form ammonia gas, which the chemical formula is NH3.The equation for the reversible reaction is:
                       N2(g) + 3H2(g) <--> 2NH3(g) + 92 kJ.
Below is a diagram of an iron oxide catalyst used in industries to produce ammonia economically.



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Uses and Raw Materials
    The Haber process is used to manufacture ammonia from nitrogen and hydrogen.  Ammonia could then be used to make nitric acid, which reacts with ammonia to create ammonium nitrate, which is a very important fertilizer.
    The raw materials for creating ammonia are air for nitrogen (N2(g)) and methane and water for hydrogen (H2(g)).
    Hydrogen is process by taking methane (CH4(g)) and reacting it with steam (H2O(g)) and thus creating carbon dioxide (CO2(g)) and hydrogen (H2(g)).
    The nitrogen (N2(g)) is obtained from the air by fractional distillation, because the air is made up of 80% nitrogen.
    Fractional distillation is where they take a substance with another substance mixed together, and since both substances have different boiling points, they heat up the mixture.  When the one substance with the lowest boiling point starts to boil it evaporates into a cooling jacket, which then liquidifies and is poured into a beaker or container. Then the next substance starts to boil and does the same thing except the substance is put into a different beaker or container to store it.  And this separates all of the components of mixtures and you can get one or more pure substances out of a mixture.



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Reversible Reactions

    When a reaction is reversible, the reaction can go either forwards or backwards.
    The FORWARD reaction is the reaction that we want, where the reactants are converted into products.  The BACKWARD reaction is where the products become the original reactants.  The reactions of both occur at the same time.
    In a CLOSED system the equilibrium mixture after awhile is reached, where a specific proportion of the mixture exists as reactants and the rest as products.  A CLOSED system is where none of the reactants or products can get out into the outside environment.
    When equilibrium has been reached it doesn't mean that the reactions have stopped.  It means that the FORWARD reaction is making products in the same amount as the BACKWARD reaction is making reactants.   This is called a DYNAMIC equilibrium.  Dynamic means moving or changing, to tell you that the reaction is till reacting.



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Le Chatelier's Principle

    For a reversible reaction, Le Chatelier's Principle states that

                         "The equilibrium position will respond
                    to oppose a change in the reaction conditions".

    Which means that is a product is removed then the equilibrium balance changes to make more of the product.  The substance then tries to go back it's original equilibrium.  then it repeats the process until nothing of the original substance is left.  This is very useful.  The reverse is also correct if you remove a reactant, the equilibrium will adjust to make more reactant, this is not useful.

    Heat may be treated as reactant (an exothermic reaction) or a product (an endothermic reaction).
    If heat is REMOVED from an exothermic reaction (cool it down) more product will be produced because the equilibrium will shift to produce it.  This will produce heat and also more chemical product that you want in the equilibrium mixture.
    If heat is ADDED to an exothermic reaction (raise it temperature) the reverse will happen and less product will be produced in the equilibrium mixture.
 

    For a reversible reaction involving gases.
    INCREASING the pressure will shift the equilibrium towards the side of the reaction, which has the smaller volume.
    DESCREASING the pressure will shift the equilibrium towards the side of the reaction that has the larger volume.



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Industrial Conditions

    The industrial conditions for producing ammonia the temperature must be 450ºC to 500ºC.  The FORWARD reaction (to form ammonia) is exothermic (it gives out heat).
    If we remove heat as a product (cooling the reaction down) will result in the equilibrium mixture making richer ammonia. (See La Chatelier's Principle)
    Since we want ammonia from the Haber Process, why is the reaction conducted at 450ºC?  Because all reactions go faster if the temperature is raised.
    Reversible reactions, such as the Haber Process, RAISING the temperature will make the equilibrium mixture richer in nitrogen and hydrogen because forming these from ammonia takes heat in.  If we COOL the reaction down the proportion of ammonia will increase but the rate of production will decrease. (because the temperature is LOWER).
    It's no good to have 90% ammonia if it takes all day to fill a bucket full, than to have 10% ammonia very quickly, having thousands of liters by the end of the day.
    Ammonia is produced at the atmospheric pressure of 100 atm because it is too expensive to make a high-pressure chemical plant.  Running the reaction at 200 atm is the highest pressure with the greatest return value.
    With a reversible reaction, a catalyst which increases the rate will increase the rate of both the forward and the backward reaction.  This is useful because the catalyst will, cause the reaction mixture to reach its equilibrium composition more quickly.  The catalyst will not change the equilibrium composition of the substance.  To see a diagram of a catalyst click on the link (catalyst diagram).



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Fertilizers
        Nitric Acid
    Nitric acid is used to react with ammonia to create ammonium nitrate, which is used as a fertilizer.  In the first stage it takes ammonia and oxygen and reacts it to create nitrogen monoxide and water.  In the second, stage the nitrogen monoxide is reacted with more oxygen to create nitrogen dioxide.  At last, the nitrogen dioxide reacts with oxygen and water to form nitric acid.  The balanced equations are:
    ammonia + oxygen  ±  nitrogen monoxide  + water.
    4NH3(g)5O2(g)  ±          4NO(g)          + 6H2O(g)
    nitrogen monoxide + oxygen   ±  nitrogen dioxide.
    2NO(g)                 +   O2(g)    ±         2NO2(g)
    nitrogen dioxide  +  oxygen   +   water      ±  nitric acid.
    4NO2(g)             +   O2(g)    +   2H2O(l)   ±  4HNO3(aq)

    The overall reaction is
    ammonia   +  oxygen        ±    nitric acid     +    water.
    4NH3(g)   +      8O2(g)     ±    4HNO3(aq)  +   4H2O(l)

        Ammonium Nitrate
    Ammonium Nitrate is the main fertilizer used.  This is created by reacting nitric acid and ammonia.

    nitric acid     +  ammonia    ±    ammonium nitrate.
    HNO3(aq)   +     NH3(g)    ±      NH4NO3(aq)

    Ammonia with sulphric acid would create ammonium sulphate.

    ammonia   +   sulphric acid    ±    ammonium sulphate.
    NH3(g)     +       HSO4(aq)     ±      (NH4)2SO4(aq)

    Ammonium nitrate has a higher percentage of nitrogen than ammonium sulphate, for the same amount of mass of fertilizer.

        Environmental Issues
    The benefits of using a nitrogenous fertilizers is obvious because the crops grow taller, and are healthier therefore yielding a higher crop and therefore cheaper, more plentiful food.
    There are always disadvantages.  These are after applying the fertilizer and it rains or too much fertilizer is used it gets into the steams or rivers and pollutes them.  In the rivers, the fertilizer does the same as it would on land, the river plants grow and algae grow rapidly because of the abundant food supply.  The algae then die in large numbers.  The bacteria feeding on the dead plant material use up the oxygen in the water.  Fish may then die because of the lack of oxygen in the water.  Also too high of nitrates in the drinking water is a health hazard, particularly with infants.  Nitrates can interfere with the oxygen flow in the blood stream.



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| Haber Process Steps | Periodic Table |
| Rejected Periodic Table |

*Note* I have not touched anything to do with the Haber Process in many years, this was a school project. Please do not email me questions, sorry for any inconvience.