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Britain & the wider world: 1745 -1901
1l the quest for political stability: germany, 1871-1991
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2d religious conflict and the church in england, c1529-c1570
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1f industrialisation and the people: britain, c1783-1885
1c the tudors: england, 1485-1603
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Chemistry
5 Dec 2025
207
3 pages
AK Squad @aksquad_hoka
Chemical changes involve reactions where metals interact with oxygen, acids, and water in predictable ways. Understanding how metals... Show more
Ever wondered why some metals rust faster than others or why gold stays shiny for centuries? It's all about reactivity - how eagerly a metal wants to lose electrons and form positive ions.
The reactivity series ranks metals from most to least reactive. Metals like potassium, sodium, and calcium sit at the top because they lose electrons really easily. Gold and platinum hang out at the bottom, barely reacting with anything.
When metals meet acids, they follow a simple pattern ACID + METAL → SALT + HYDROGEN. You can actually see how reactive a metal is by watching how fast the hydrogen bubbles form. Potassium reacts explosively (don't try this at home!), whilst copper barely bothers to react with cold, dilute acids.
Metal extraction depends entirely on where a metal sits in this series. If it's below carbon (like zinc or iron), we can use carbon to extract it cheaply. Metals above carbon need expensive electrolysis to extract them - that's why aluminium used to be more valuable than gold!
Quick Tip Remember OIL RIG - Oxidation Is Loss (of electrons), Reduction Is Gain (of electrons). This helps you identify what's happening in metal reactions.
Redox reactions are everywhere in chemistry - they're simply reactions where electrons move from one substance to another. The name comes from REDuction and OXidation happening simultaneously.
Displacement reactions are brilliant examples of redox in action. A more reactive metal literally kicks a less reactive metal out of its compound. Think of it like queue-jumping - the more aggressive metal takes the place of the weaker one.
Here's what happens when you drop iron into copper sulphate solution, the iron loses electrons (gets oxidised) whilst the copper ions gain those electrons (get reduced). You'll see the blue solution turn colourless as shiny copper metal appears.
Ionic equations make these reactions clearer by showing only the particles that actually change. The spectator ions (like chloride ions that don't react) get ignored - they're just watching from the sidelines.
Real-World Connection Displacement reactions happen in galvanising (coating iron with zinc) and in extracting metals from ores. Understanding this helps explain why some metals are better for certain jobs.
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.
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Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore the reactivity series of metals, oxidation and reduction processes, and the formation of salts through various chemical reactions. This summary covers key concepts such as displacement reactions, redox reactions, and the extraction of metals, tailored for AQA GCSE Combined Science Chemistry students. Understand how metals react with water, acids, and their oxides, along with essential equations and definitions.
ChemistryExplore the fundamentals of ionic bonding and atomic structure in this detailed summary. Understand how metals and non-metals interact to form ionic compounds, the role of subatomic particles, and the concept of isotopes. Ideal for students seeking clarity on atomic theory and bonding concepts.
ChemistryExplore the process of electrolysis, including key concepts such as oxidation, reduction, and the roles of the anode and cathode. This summary provides a clear overview of how electric current decomposes ionic compounds in electrolytic cells, supported by diagrams for better understanding.
ChemistryExplore the process of electrolysis for metal extraction, focusing on aluminium and lead. Understand key concepts such as electrodes, electrolytes, and half-reactions. This summary covers the principles of electrolysis, including the roles of the cathode and anode, and the reactions involved in both molten and aqueous solutions. Ideal for AQA GCSE Chemistry students preparing for paper 1.
ChemistryExplore the fundamentals of ionic compounds, chemical bonding, and the principles of mixtures in this comprehensive study note. Ideal for GCSE Chemistry students, this resource covers key concepts such as ionic and covalent bonds, separation techniques like chromatography, and the behavior of atoms in reactions. Enhance your understanding of chemical principles and prepare effectively for your exams.
ChemistryExplore key concepts of electrolysis, including ionic and covalent bonding, Faraday's Law, and the production of metals like aluminum. This resource features exam questions and answers to enhance your understanding of electrochemical processes and their applications in metal extraction and alloy formation.
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
AK Squad
@aksquad_hoka
Chemical changes involve reactions where metals interact with oxygen, acids, and water in predictable ways. Understanding how metals behave in these reactions helps us extract useful materials and predict what happens when different substances meet.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Ever wondered why some metals rust faster than others or why gold stays shiny for centuries? It's all about reactivity - how eagerly a metal wants to lose electrons and form positive ions.
The reactivity series ranks metals from most to least reactive. Metals like potassium, sodium, and calcium sit at the top because they lose electrons really easily. Gold and platinum hang out at the bottom, barely reacting with anything.
When metals meet acids, they follow a simple pattern: ACID + METAL → SALT + HYDROGEN. You can actually see how reactive a metal is by watching how fast the hydrogen bubbles form. Potassium reacts explosively (don't try this at home!), whilst copper barely bothers to react with cold, dilute acids.
Metal extraction depends entirely on where a metal sits in this series. If it's below carbon (like zinc or iron), we can use carbon to extract it cheaply. Metals above carbon need expensive electrolysis to extract them - that's why aluminium used to be more valuable than gold!
Quick Tip: Remember OIL RIG - Oxidation Is Loss (of electrons), Reduction Is Gain (of electrons). This helps you identify what's happening in metal reactions.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Redox reactions are everywhere in chemistry - they're simply reactions where electrons move from one substance to another. The name comes from REDuction and OXidation happening simultaneously.
Displacement reactions are brilliant examples of redox in action. A more reactive metal literally kicks a less reactive metal out of its compound. Think of it like queue-jumping - the more aggressive metal takes the place of the weaker one.
Here's what happens: when you drop iron into copper sulphate solution, the iron loses electrons (gets oxidised) whilst the copper ions gain those electrons (get reduced). You'll see the blue solution turn colourless as shiny copper metal appears.
Ionic equations make these reactions clearer by showing only the particles that actually change. The spectator ions (like chloride ions that don't react) get ignored - they're just watching from the sidelines.
Real-World Connection: Displacement reactions happen in galvanising (coating iron with zinc) and in extracting metals from ores. Understanding this helps explain why some metals are better for certain jobs.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
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.
3
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore the reactivity series of metals, oxidation and reduction processes, and the formation of salts through various chemical reactions. This summary covers key concepts such as displacement reactions, redox reactions, and the extraction of metals, tailored for AQA GCSE Combined Science Chemistry students. Understand how metals react with water, acids, and their oxides, along with essential equations and definitions.
ChemistryExplore the fundamentals of ionic bonding and atomic structure in this detailed summary. Understand how metals and non-metals interact to form ionic compounds, the role of subatomic particles, and the concept of isotopes. Ideal for students seeking clarity on atomic theory and bonding concepts.
ChemistryExplore the process of electrolysis, including key concepts such as oxidation, reduction, and the roles of the anode and cathode. This summary provides a clear overview of how electric current decomposes ionic compounds in electrolytic cells, supported by diagrams for better understanding.
ChemistryExplore the process of electrolysis for metal extraction, focusing on aluminium and lead. Understand key concepts such as electrodes, electrolytes, and half-reactions. This summary covers the principles of electrolysis, including the roles of the cathode and anode, and the reactions involved in both molten and aqueous solutions. Ideal for AQA GCSE Chemistry students preparing for paper 1.
ChemistryExplore the fundamentals of ionic compounds, chemical bonding, and the principles of mixtures in this comprehensive study note. Ideal for GCSE Chemistry students, this resource covers key concepts such as ionic and covalent bonds, separation techniques like chromatography, and the behavior of atoms in reactions. Enhance your understanding of chemical principles and prepare effectively for your exams.
ChemistryExplore key concepts of electrolysis, including ionic and covalent bonding, Faraday's Law, and the production of metals like aluminum. This resource features exam questions and answers to enhance your understanding of electrochemical processes and their applications in metal extraction and alloy formation.
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