1. The Haber Process During the first decade of the twentieth century the world-wide demand for ammonia for use in fertilisers (in the form of nitrates) and in the production of explosives for use in mining and warfare could only be satisfied on a large scale from deposits of guano in Chile (2). Though this deposit was of huge size (approximately five feet thick and 385 kilometres long) it represented a rapidly depleting resource when compared to world-wide demand. As a result of this there was much research into how ammonia could be produced from atmospheric nitrogen. The problem was eventually solved by Fritz Haber (1868 - 1934) in a process which came to be known as the "Haber Process" or the "Haber - Bosch Process". Haber developed a method for synthesising ammonia utilising atmospheric nitrogen and had established the conditions for large scale synthesis of ammonia by 1909 and the process was handed over to Carl Bosch for industrial development (1). the reaction is a simple equilibrium reaction which occurs in gaseous state as follows; N2 (g) + 3H2 (g) = 2NH3 (g) heat of enthalpy = -92.6 kJ/mol In predicting how to obtain the highest yield from this reaction we must refer to Le Chatlier's Principle. This states that for an equilibrium reaction the equilibrium will work in the opposite direction to the conditions forced upon it. The conditions most pertinent to the above reaction are temperature and pressure. The pressure exerted by any gas or mixture of gasses in an enclosed space is directly proportional to the number of atoms or molecules of gas regardless of their size or molecular mass. Reference to the above reaction shows that, as the reaction moves to the right the number of molecules and hence the pressure decreases. Therefore the reaction moving to the right (i.e. towards the product required) is favoured by an increase in pressure. With regard to temperature, the reaction moving to the right is exothermic i.e. it gives off energy (in the form of heat). Therefore reference to Le Chatlier's Principle shows that the reaction to the right is favoured by low temperatures. However, when Haber placed the reactants together under these conditions it was shown that the rate of reaction was so slow as to render the process unfeasible as an industrial process. This is because of an unusually high activation energy. The activation energy of a reaction is the energy required by the reactants to achieve an intermediate state required before they form the products.
The most important concept that should be taken from this lab is that the limiting reactant restricts the amount of product possible from a reaction. Increasing the amounts of other reactants will not increase the amount of product, but increasing the amount of the limiting reactant will.
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Together with his father he performed experiments to develop nitroglycerine as a commercially and technically useful explosive. They did have a few accidents where several explosions did happen, including one in which his brother Emil and several other persons were killed. This convinced the authorities of the city that nitroglycerine production was just too dangerous. So they forbade further experimentation with nitroglycerine in the Stockholm city limits and he had to move his experimentation to a barge anchored on a lake. But of course Alfred was not discouraged and in 1864 he was able to start mass production of nitroglycerine. To make the handling of nitroglycerine safer he experimented with different additives. He soon found that mixing nitroglycerine with silica would turn the liquid into a paste, which could be shaped into rods, which could be dropped into drilled holes in rocks. In 1867 he patented this material under the name of dynamite. By the time of his death in 1896 he had 355 patents.
anyway) Note these factors affect the rate of the reaction, but not the final. amount of carbon dioxide produced). Why these factors affect it: higher temperature makes atoms move more. so they are more likely to bump into each other and react.
... This is related to Gay –Lussac’s Law. This is because temperature is the same thing as kinetic energy, and as the energy rises, the particles within the substance start to rapidly collide with one another, and they exert increased pressure. This law is written as:.
In able to produce ammonia, nitrogen and hydrogen gas mixture composed together under high temperature, high pressure conditions and the role of catalyst. In the spirit of perseverance, through continuous experiments and calculations, Haber finally achieved encouraging results in 1909. When the temperature is 600 degree Celsius, under the conditions of 200 atmospheric pressure and osmium catalyst, the yield was approximately 8% of ammonia. 8% conversion rate is not considered high; it will obviously affect economic production. Haber known ammonia production cannot attain high conversion rate like sulfuric acid. Haber cons...
Water gas shift reaction was first exposed and practiced by Italian entrepreneur and physicist Fenice Fontana in 1780. Through his extension of understood chemical and physical properties of gases, he utilized the WGSR to produce cost efficient hydrogen production. The reactants contained syngas or water gas, carbon monoxide and hydrogen mixture. WGSR was expanded in 1873 by Thaddeus S.C. Lowe, where he used water gas-shift reaction with high pressured steam and coke gas to produce an excessive amount of hydrogen gas. Today, water gas shift reactions have been intertwined with syngas to produce the same products, though, at an increased demand with increases in production from catalyst involvement.
As the temperature increases, the movements of molecules also increase. This is the kinetic theory. When the temperature is increased the particles gain more energy and therefore move around faster. This gives the particles more of a chance with other particles and with more force.
• An increase in the temperature of the system will increase the rate of reaction. Again, using the Maxwell-Boltzmann distribution diagram, we can see how the temperature affects the reaction rate by seeing that an increase in temperature increases the average amount of energy of the reacting particles, thus giving more particles sufficient energy to react.
5. In a gas increasing the pressure means molecules are more squashed up together, so there will be more collisions. My Investigation. I am going to investigate the concentration variable. I have chosen this because in my opinion it will be the easiest one to measure.
Looking at the table of results above and the graph, it is shown that the higher the temperature got, the shorter the reaction time. The obtained results have been plotted on a line graph of the temperature of hydrochloric acid (y-axis) against reaction time (x-axis). This line graph in fig.2 also clearly shows that as the temperature increases, so does the speed of the reaction, shown by a reduction in the time taken. This corroborates the collision theory, where as the temperature of particles increase, the particles gain more kinetic energy and react with each other upon collision. This is shown as to happen in the hydrochloric acid, where the hydrochloric acid particles collide more with the particles of the magnesium ribbon as the temperature was increased. The above graph shows a gradual sloping curve, which gets steeper at higher temperatures. This shows that the reaction will reach a peak rate of activity as the gaps between the temperature and reaction times continue to decrease. The experiment fulfills the aim and clearly shows that as the temperature of a reaction is increased so does it’s rate of reaction, proving the hypothesis to be correct.
Reactions occur when the particles of reactants collide together continuously. If they collide with sufficient energy, then they will react. The minimum amount of kinetic energy required for particles at the time of collision is called the activation energy and this theory is known as the ?collision theory?.
that the rate of reaction must be fast enough to make as much of the
There are five factors which affect the rate of a reaction, according to the collision theory of reacting particles: temperature, concentration (of solution), pressure (in gases), surface area (of solid reactants), and catalysts. I have chosen to investigate the effect of concentration on the rate of reaction. This is because it is the most practical way to investigate. Dealing with temperatures is a difficult task, especially when we have to keep constant high temperatures. Secondly, the rate equation and the constant k changes when the temperature of the reaction changes.
To control the rates of chemical reactions is imperative to the continued existence of our species. Controlled chemical reactions allow us to move forward in society, constantly. We find new ways to provide light and heat our homes, cook our food, and pursue in crafts that benefit our society. There are, however, just as there are advantages, disadvantages to the efficiency of controlling the rate of reactions, which in some cases can be fatal to our scientific development and progression. The growth of humankind necessitates that we must be able to control the rate of chemical reactions.