Know that an Iron Catalyst is used during the Haber Process Explain the choice of temperature and pressure used Explain the importance of recycling the Nitrogen and Hydrogen

N2 + H2 NH3 1.Balance the Equation 2.Name the catalyst missing from the equation 3.Explain how the catalyst affects the reaction

A catalyst will lower the activation energy - hence increases the reaction rate, while remaining chemically unchanged at the end of the reaction. CatalystNo Catalyst Amount Added Nitrogen + Hydrogen = Ammonia Activation Energy with a: Show instructions Hide instructions Click on the words to show how they will be represented on the graph

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The forward reaction is exothermic so if we carry out the reaction at a lower temperature we will get a higher yield of ammonia. When the temperature is low the reaction is slow, in industry time is money ! A compromise is made with the temperature. To ensure a reasonable yield is collected at a reasonable rate, a reasonably high temperature is used. The higher the pressure the higher the yield. However, high pressures are expensive and dangerous. A compromise is made with the pressure. The company will weigh up the cost of the high pressure with the yield produced. This usually means the pressure is between 200 and 350 atm. On each pass through the process only about 15% conversion occurs, but any unreacted gases are recycled, so that eventually an overall conversion of 98% can be achieved. This is why recycling the gases is so important.

What temperature gives the highest yield What pressure gives the highest yield Why use a catalyst? What does a low temperature produce Explain the reasons for using a reasonably high temperature in industry Explain the reasons for using a pressure between 200 – 350 atm in industry Why recycle the Nitrogen and Hydrogen? Show instructions Hide instructions Think – Pair share and peer marking could be used for pupils to obtain their answer

FACTORY FANTASIE’S Manage your own Haber Processing Factory Choose your upgrades Get a Porsche for your Bonus You set the Temperature, Pressure, Workers Pay! Aim: You choose! Show instructions Hide instructions Click on the green button at the bottom of the screen

FACTORY FANTASIE’S Stage One..... Choose your site... FACTORY FANTASIE’S Stage Two..... Choose your manager... and set the Pay! (be careful, each manager has their own advantages and disadvantages). Show instructions Hide instructions Click Activity Suggestion to gain an insight into the activity Click on the left green oval Click on the right green oval Activity Suggestion Pupils create a game based on running a factory that allows the gamer to control everything i.e. increase pressure to a very high point allowing them to maximise the yield, however this will be very costly. The bosses can have different methods if they use the example to start them off (for example, one boss could be a risk taker, another very focused on cost, another very focused on the yield and not worried about money). It will be up to the teacher to decide the limitations. There are numerous ways to make the activity varied. After this the pupils can switch their game designs with each other. This is just a suggestion, an example to give the pupils an idea

FACTORY FANTASIE’S Stage Three..... Set the Temperature... FACTORY FANTASIE’S Stage Four..... Set the Pressure... Show instructions Hide instructions Click lesson idea to gain an insight into the activity Click on the left green oval Click on the right green oval

FACTORY FANTASIE’S Final Stage...Produce a Report.. How much Ammonia will you make? How Quickly will you produce the ammonia? Have you remembered to use a catalyst? Will your plant be able to run for years to come? Have you made it too expensive? What conditions did you choose?

To Summarize An Iron catalyst is used in the Haber Process A compromise is made for the conditions of the reaction. 450 and 200 – 350atm. For an efficient conversion It is very important that the unused Nitrogen and Hydrogen is recycled back into the reaction I can’t wait to get on my Pear Pad when I get home... I will get the best yield this time?