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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
2o democracy and nazism: germany, 1918-1945
1f industrialisation and the people: britain, c1783-1885
1c the tudors: england, 1485-1603
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2s the making of modern britain, 1951-2007
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Chemistry
5 Dec 2025
194
3 pages
hannah @hannah.revise
Chemistry might seem complicated, but understanding how metals behave is actually quite straightforward once you know the patterns.... Show more
Ever wonder why some metals rust quickly whilst others stay shiny for years? It all comes down to reactivity - how eager metals are to lose electrons and form compounds.
Oxidation happens when metals gain oxygen or lose electrons. Think of it as metals "giving away" their electrons because they're generous like that. The more reactive a metal is, the more easily this happens.
Reduction is the opposite - it's when substances lose oxygen or gain electrons. Remember it as metals being "reduced" in their eagerness to react.
Quick Tip Use the phrase "OIL RIG" - Oxidation Is Loss (of electrons), Reduction Is Gain (of electrons)!
The reactivity series is like a league table for metals, ranking them from most to least reactive. At the top, you've got potassium and sodium (seriously reactive), whilst gold and platinum chill at the bottom being practically unreactive.
Here's the order you need to know Potassium, Sodium, Lithium, Calcium, Magnesium, Aluminium, Zinc, Iron, Copper, Silver, Gold, Platinum. The higher up the list, the more likely that metal is to lose electrons and form positive ions.
Displacement reactions happen when a more reactive metal kicks out a less reactive one from a compound. For example, magnesium can displace copper from copper sulfate because magnesium is higher in the reactivity series. It's like a stronger player taking someone else's position on the team.
Memory Trick "Please Stop Lithium Calling My Aunt Zelda In Copper Silver Gloves Please" - use this to remember the reactivity series order!
When metals meet acids, they create a salt plus hydrogen gas - it's one of the most predictable reactions in chemistry. This is also a redox reaction because the metal gets oxidised whilst the acid gets reduced.
Neutralisation happens when acids react with bases (anything with a pH above 7). You'll encounter three main types of bases metal carbonates, metal oxides, and metal hydroxides. Each creates a slightly different reaction pattern.
Metal carbonates give you salt + water + carbon dioxide. Metal hydroxides produce salt + water. Metal oxides also create salt + water. The key is recognising which type of base you're dealing with, then you can predict the products every time.
Exam Tip Always check if carbon dioxide is produced - it's the telltale sign you're dealing with a carbonate reaction!
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.
1
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Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore the fundamentals of acid-base reactions, including neutralization, titrations, and the formation of salts. This summary covers key concepts such as pH, redox reactions, and the reactivity series, providing essential insights for AQA GCSE Chemistry students. Ideal for exam preparation and understanding chemical changes.
ChemistryExplore the reactivity of metals through redox reactions, displacement reactions, and half equations. This summary covers key concepts such as alkali metals, oxidation, and reduction, tailored for Edexcel Chemistry Paper 1. Understand how more reactive metals displace less reactive ones and the significance of ionic equations in chemical reactions.
ChemistryExplore the properties and reactivity of Group 1 (Alkali Metals), Group 0 (Noble Gases), Group 7 (Halogens), and Transition Metals. This summary covers key characteristics, reactions, and trends within the periodic table, making it essential for GCSE Chemistry students. Understand how these groups compare and their significance in chemical reactions.
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
hannah
@hannah.revise
Chemistry might seem complicated, but understanding how metals behave is actually quite straightforward once you know the patterns. Let's break down metal reactivity, displacement reactions, and how metals interact with acids - concepts that'll pop up regularly in your GCSE... Show more
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Ever wonder why some metals rust quickly whilst others stay shiny for years? It all comes down to reactivity - how eager metals are to lose electrons and form compounds.
Oxidation happens when metals gain oxygen or lose electrons. Think of it as metals "giving away" their electrons because they're generous like that. The more reactive a metal is, the more easily this happens.
Reduction is the opposite - it's when substances lose oxygen or gain electrons. Remember it as metals being "reduced" in their eagerness to react.
Quick Tip: Use the phrase "OIL RIG" - Oxidation Is Loss (of electrons), Reduction Is Gain (of electrons)!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
The reactivity series is like a league table for metals, ranking them from most to least reactive. At the top, you've got potassium and sodium (seriously reactive), whilst gold and platinum chill at the bottom being practically unreactive.
Here's the order you need to know: Potassium, Sodium, Lithium, Calcium, Magnesium, Aluminium, Zinc, Iron, Copper, Silver, Gold, Platinum. The higher up the list, the more likely that metal is to lose electrons and form positive ions.
Displacement reactions happen when a more reactive metal kicks out a less reactive one from a compound. For example, magnesium can displace copper from copper sulfate because magnesium is higher in the reactivity series. It's like a stronger player taking someone else's position on the team.
Memory Trick: "Please Stop Lithium Calling My Aunt Zelda In Copper Silver Gloves Please" - use this to remember the reactivity series order!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
When metals meet acids, they create a salt plus hydrogen gas - it's one of the most predictable reactions in chemistry. This is also a redox reaction because the metal gets oxidised whilst the acid gets reduced.
Neutralisation happens when acids react with bases (anything with a pH above 7). You'll encounter three main types of bases: metal carbonates, metal oxides, and metal hydroxides. Each creates a slightly different reaction pattern.
Metal carbonates give you salt + water + carbon dioxide. Metal hydroxides produce salt + water. Metal oxides also create salt + water. The key is recognising which type of base you're dealing with, then you can predict the products every time.
Exam Tip: Always check if carbon dioxide is produced - it's the telltale sign you're dealing with a carbonate reaction!
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.
1
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore the fundamentals of acid-base reactions, including neutralization, titrations, and the formation of salts. This summary covers key concepts such as pH, redox reactions, and the reactivity series, providing essential insights for AQA GCSE Chemistry students. Ideal for exam preparation and understanding chemical changes.
ChemistryExplore the reactivity of metals through redox reactions, displacement reactions, and half equations. This summary covers key concepts such as alkali metals, oxidation, and reduction, tailored for Edexcel Chemistry Paper 1. Understand how more reactive metals displace less reactive ones and the significance of ionic equations in chemical reactions.
ChemistryExplore the properties and reactivity of Group 1 (Alkali Metals), Group 0 (Noble Gases), Group 7 (Halogens), and Transition Metals. This summary covers key characteristics, reactions, and trends within the periodic table, making it essential for GCSE Chemistry students. Understand how these groups compare and their significance in chemical reactions.
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