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Britain & the wider world: 1745 -1901
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Chemistry
14 Dec 2025
89
3 pages
Tara Vidal @taravidal_jrny
The Haber processis one of the most important industrial reactions in the world, turning nitrogen from air... Show more
Ever wondered how we make enough food to feed the world's population? The Haber process is the answer - it manufactures ammonia from nitrogen and hydrogen using an iron catalyst. This might sound simple, but it's actually a carefully balanced industrial process.
The reactants come from surprisingly everyday sources. Nitrogen comes straight from the air around us, whilst hydrogen is produced by reacting methane (natural gas) with steam. It's brilliant how we can use such common materials to create something so essential.
The process is exothermic, meaning it releases heat energy. However, there's a clever compromise at play - the reaction runs at 450°C, which might seem hot but is actually a middle ground. Lower temperatures would give more ammonia but make the reaction painfully slow, so 450°C gives a decent yield at a reasonable speed.
Key Point The Haber process uses a compromise temperature because you need to balance getting a good yield with keeping the reaction fast enough to be practical.
Your plants need proper nutrition just like you do, and NPK fertilisers are like vitamin supplements for crops. NPK stands for nitrogen, phosphorus, and potassium - the three essential elements that help plants grow rapidly and stay healthy.
These fertilisers are formulations containing salts of N, P, and K in exactly the right percentages. Ammonium nitrate is a perfect example - it's made by using ammonia from the Haber process to produce nitric acid, which then reacts with more ammonia. It's like a chemical assembly line.
Potassium sources come from potassium chloride or potassium sulfate, which are simply mined from the ground with no further processing needed. For phosphorus, things get more interesting - phosphate rock reacts with nitric acid to make phosphoric acid, but plants can't use this directly, so it's neutralised with ammonia to create ammonium phosphate.
Key Point Different combinations create different fertiliser products - phosphate rock with sulfuric acid makes single superphosphate, whilst phosphate rock with phosphoric acid creates triple superphosphate.
Making fertilisers in your school lab versus in a massive factory is like comparing a bicycle to a Formula 1 car. In school, you'll use dilute ammonia and nitric acid, heat things up with a trusty Bunsen burner, and work in small batch processes that only make tiny amounts at a time.
Industry takes everything up to eleven. They use concentrated acids and gaseous ammonia, which makes the process far more dangerous since the reaction becomes incredibly exothermic. The heat produced is so intense it could be dangerous, but clever engineers safely remove this heat and use it in later stages of the process.
The biggest difference is that industry runs continuous processes rather than batch processes. This means they never stop producing - it's like a 24/7 fertiliser factory that achieves much higher yields and better energy efficiency through evaporation methods.
Key Point Industrial processes are more dangerous due to concentrated chemicals and intense heat, but they're also far more efficient and productive than anything possible in a school lab.
Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.
You can download the app from Google Play Store and Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
2
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore the principles of energy changes in chemical reactions, focusing on exothermic and endothermic processes, bond energy, and calorimetry techniques. This summary covers key concepts such as activation energy, collision theory, and the functioning of fuel cells and batteries. Ideal for GCSE Chemistry students preparing for AQA Higher Triple exams.
ChemistryExplore the principles of reversible reactions and dynamic equilibrium in AQA Chemistry. This summary covers Le Chatelier's principle, the effects of concentration, temperature, and pressure changes on equilibrium, and the characteristics of exothermic and endothermic reactions. Ideal for students preparing for exams.
ChemistryExplore the principles of chemical equilibrium, including Le Chatelier's Principle, factors affecting reaction rates, and the impact of concentration and pressure changes. This summary provides a clear overview of how systems respond to changes, ideal for GCSE Chemistry students preparing for exams.
ChemistryExplore the fundamentals of chemical bonding, including ionic and covalent structures. This study note covers energy changes in reactions, the characteristics of giant covalent structures like diamond and graphite, and the principles of ionic bonding with detailed diagrams. Ideal for students preparing for exams in chemistry.
ChemistryExplore the fundamentals of energy changes in chemical reactions, including exothermic and endothermic processes, bond energies, and practical applications like fuel cells and electrochemical cells. This summary is ideal for AQA GCSE students preparing for exams, featuring key concepts and practical insights to enhance understanding.
ChemistryExplore the concepts of exothermic and endothermic reactions, including activation energy and energy transfer. This summary covers key definitions, energy profiles, and real-world examples such as combustion and thermal decomposition. Ideal for GCSE Chemistry students preparing for exams.
ChemistryApp Store
Google Play
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
Tara Vidal
@taravidal_jrny
The Haber processis one of the most important industrial reactions in the world, turning nitrogen from air and hydrogen into ammonia for fertilisers. Understanding how this process works and how it's used to make NPK fertilisers is crucial for... Show more
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Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Ever wondered how we make enough food to feed the world's population? The Haber process is the answer - it manufactures ammonia from nitrogen and hydrogen using an iron catalyst. This might sound simple, but it's actually a carefully balanced industrial process.
The reactants come from surprisingly everyday sources. Nitrogen comes straight from the air around us, whilst hydrogen is produced by reacting methane (natural gas) with steam. It's brilliant how we can use such common materials to create something so essential.
The process is exothermic, meaning it releases heat energy. However, there's a clever compromise at play - the reaction runs at 450°C, which might seem hot but is actually a middle ground. Lower temperatures would give more ammonia but make the reaction painfully slow, so 450°C gives a decent yield at a reasonable speed.
Key Point: The Haber process uses a compromise temperature because you need to balance getting a good yield with keeping the reaction fast enough to be practical.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Your plants need proper nutrition just like you do, and NPK fertilisers are like vitamin supplements for crops. NPK stands for nitrogen, phosphorus, and potassium - the three essential elements that help plants grow rapidly and stay healthy.
These fertilisers are formulations containing salts of N, P, and K in exactly the right percentages. Ammonium nitrate is a perfect example - it's made by using ammonia from the Haber process to produce nitric acid, which then reacts with more ammonia. It's like a chemical assembly line.
Potassium sources come from potassium chloride or potassium sulfate, which are simply mined from the ground with no further processing needed. For phosphorus, things get more interesting - phosphate rock reacts with nitric acid to make phosphoric acid, but plants can't use this directly, so it's neutralised with ammonia to create ammonium phosphate.
Key Point: Different combinations create different fertiliser products - phosphate rock with sulfuric acid makes single superphosphate, whilst phosphate rock with phosphoric acid creates triple superphosphate.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Making fertilisers in your school lab versus in a massive factory is like comparing a bicycle to a Formula 1 car. In school, you'll use dilute ammonia and nitric acid, heat things up with a trusty Bunsen burner, and work in small batch processes that only make tiny amounts at a time.
Industry takes everything up to eleven. They use concentrated acids and gaseous ammonia, which makes the process far more dangerous since the reaction becomes incredibly exothermic. The heat produced is so intense it could be dangerous, but clever engineers safely remove this heat and use it in later stages of the process.
The biggest difference is that industry runs continuous processes rather than batch processes. This means they never stop producing - it's like a 24/7 fertiliser factory that achieves much higher yields and better energy efficiency through evaporation methods.
Key Point: Industrial processes are more dangerous due to concentrated chemicals and intense heat, but they're also far more efficient and productive than anything possible in a school lab.
Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.
You can download the app from Google Play Store and Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
2
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore the principles of energy changes in chemical reactions, focusing on exothermic and endothermic processes, bond energy, and calorimetry techniques. This summary covers key concepts such as activation energy, collision theory, and the functioning of fuel cells and batteries. Ideal for GCSE Chemistry students preparing for AQA Higher Triple exams.
ChemistryExplore the principles of reversible reactions and dynamic equilibrium in AQA Chemistry. This summary covers Le Chatelier's principle, the effects of concentration, temperature, and pressure changes on equilibrium, and the characteristics of exothermic and endothermic reactions. Ideal for students preparing for exams.
ChemistryExplore the principles of chemical equilibrium, including Le Chatelier's Principle, factors affecting reaction rates, and the impact of concentration and pressure changes. This summary provides a clear overview of how systems respond to changes, ideal for GCSE Chemistry students preparing for exams.
ChemistryExplore the fundamentals of chemical bonding, including ionic and covalent structures. This study note covers energy changes in reactions, the characteristics of giant covalent structures like diamond and graphite, and the principles of ionic bonding with detailed diagrams. Ideal for students preparing for exams in chemistry.
ChemistryExplore the fundamentals of energy changes in chemical reactions, including exothermic and endothermic processes, bond energies, and practical applications like fuel cells and electrochemical cells. This summary is ideal for AQA GCSE students preparing for exams, featuring key concepts and practical insights to enhance understanding.
ChemistryExplore the concepts of exothermic and endothermic reactions, including activation energy and energy transfer. This summary covers key definitions, energy profiles, and real-world examples such as combustion and thermal decomposition. Ideal for GCSE Chemistry students preparing for exams.
ChemistryApp Store
Google Play
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
Sociology