Equilibrium of importance is the importance of compromise between the amount of product you get out of the reaction & the money that you will save.
This is particularly important in the chemical industry.
Example: The Haber process
The Haber process is a process at which you can get ammonia from nitrogen in the air reacting with hydrogen. This is so that fertilisers can be produced.
The reaction of nitrogen to hydrogen to produce ammonia
However there is a problem to the reaction of these 2 elements. The problem is that the nitrogen is very unreactive. Also the reaction is exothermic so it is very hard to break the triple nitrogen to nitrogen bond
Nitrogen molecule showing the triple bond
With this problem in mind, chemists ask the question
"How can an industrial plant be set up to give a good yield of ammonia at an acceptable rate?"(quoted from the ocr book).
We can do this by using a Iron catalyst.
However, another solution to the problem might be to increase the temperature of the reaction. But by using Le Chatelier's principle the reaction is exothermic, so the increase in temperature will drive the equilibrium to the left. This will mean that the there will be more reactants.
Another way is to increase the pressure. So by using Le Chatelier's principle, the increase in pressure will put the equilibrium to the right making more ammonia.
However the idea is good in theory, but in practice it isn't very effective money wise. This is because by using very high pressures it increases the cost of the factory, sue to the fact there will be more maintenance, and the costs of labour will increase. But by putting catalysts in it, the catalysts can provide a alternate route with lower activation energy. This increases the rate of reaction but does not effect the equilibrium.
So in conclusion the way that an ammonia producing factory should work in is that the pressure should be fairy high(but not too high due to costs) and the temperature should be high enough to produce a reasonable yield. This temperature is named the compromise temperature. Also catalysts should be added to improve the rate of reaction.
So in conclusion the equilibrium of importance is the compromise what what factors you can change to a reaction to produce more of the product to the money you will save fro not increasing those factors.
Questions from the book.
A modern Haber process plant may operate at a temperature of 450 degrees,a pressure of 100 atm, and using a iron catalyst.
a) Why don't they use a temperature above 450 degrees b) Why don't they use a temperature below 450 degrees c) Why don't they use a pressure above 100 atm d) Why don't they use a pressure below 100 atm