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Britain & the wider world: 1745 -1901
1l the quest for political stability: germany, 1871-1991
The cold war
Inter-war germany
Medieval period: 1066 -1509
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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Chemistry
13 Dec 2025
259
4 pages
Mary McGarrigle @mary.mcg
The reactivity series is your roadmap to understanding how metals behave - it shows which metals are chemical... Show more
Think of the reactivity series as a league table for metals - potassium sits at the top as the most reactive troublemaker, whilst gold and silver chill at the bottom as the least reactive. The key rule? More reactive metals lose their outer shell electrons more easily, making them desperate to react with anything nearby.
When metals meet air, they gain mass and form oxides - it's like they're putting on protective coats! You'll see spectacular coloured flames potassium burns with a lilac flame, sodium glows yellow-orange, and magnesium produces that brilliant white light that'll make you squint.
The most reactive metals (potassium, sodium, calcium) are so dangerous that you won't handle them in school labs. Copper won't even burn properly - it just sits there looking shiny until it slowly tarnishes.
Quick Tip Remember "K Na Ca Mg Al Zn Fe Cu Au Ag" - this order will save you in every test question!
Water reactions get seriously dramatic with the most reactive metals. Potassium literally has a tantrum - it floats, fizzes, produces a lilac flame, and sometimes explodes with crackling sounds before disappearing completely. Sodium's slightly more civilised but still melts into a silvery ball whilst dancing around the surface.
Calcium sinks first (like it's thinking about it) then rises up bubbling away. Magnesium barely bothers - just a few lazy bubbles over ages. Notice the pattern in the equations Metal + Water → Metal Hydroxide + Hydrogen.
The hydrogen gas produced is what causes all that fizzing and bubbling. Potassium and sodium are so reactive they're stored under oil - otherwise they'd react with moisture in the air before you could even use them!
Safety First These reactions release heat and produce flammable hydrogen gas - that's why we use safety screens and tongs.
When metals meet steam (water's angry cousin), even the less reactive ones join the party. The key difference? Steam reactions produce metal oxides instead of metal hydroxides - so the equation becomes Metal + Steam → Metal Oxide + Hydrogen.
Magnesium ribbon burns with that signature bright white light, creating white solid magnesium oxide. Aluminium powder burns too, but it's got a sneaky protective oxide layer that usually keeps it safe from reactions. Zinc powder glows yellow when hot but turns white when it cools down.
Even iron gets involved with steam - the powder glows red-hot and produces black iron oxide. The experimental setup uses mineral wool soaked in water that gets heated to produce steam, which then flows over the heated metal.
Remember Steam packs more energy than liquid water, so it can persuade less reactive metals to join in the fun.
Displacement reactions are like chemical bullying - a more reactive metal kicks a less reactive one out of its compound and takes its place. These reactions are exothermic, so they'll warm up your test tube nicely.
The displacement table shows the results clearly put zinc into copper sulphate solution and you'll see a red-brown layer of copper forming whilst the blue colour fades (because the copper ions are leaving the solution). The further apart the metals are on the reactivity series, the faster and more exothermic the reaction becomes.
This concept explains metal extraction methods too. Metals high up in the reactivity series (like aluminium) need electrolysis to extract them because they're so stubborn about giving up their electrons. Less reactive metals can be extracted by reduction - a much gentler approach.
Test Tip In exams, you'll often get a table showing displacement results - just remember that only more reactive metals can displace less reactive ones!
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.
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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
Mary McGarrigle
@mary.mcg
The reactivity series is your roadmap to understanding how metals behave - it shows which metals are chemical hotshots and which are more laid-back. Once you've got this series memorised, you'll be able to predict what happens when metals meet... Show more
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Join milions of students
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Think of the reactivity series as a league table for metals - potassium sits at the top as the most reactive troublemaker, whilst gold and silver chill at the bottom as the least reactive. The key rule? More reactive metals lose their outer shell electrons more easily, making them desperate to react with anything nearby.
When metals meet air, they gain mass and form oxides - it's like they're putting on protective coats! You'll see spectacular coloured flames: potassium burns with a lilac flame, sodium glows yellow-orange, and magnesium produces that brilliant white light that'll make you squint.
The most reactive metals (potassium, sodium, calcium) are so dangerous that you won't handle them in school labs. Copper won't even burn properly - it just sits there looking shiny until it slowly tarnishes.
Quick Tip: Remember "K Na Ca Mg Al Zn Fe Cu Au Ag" - this order will save you in every test question!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Water reactions get seriously dramatic with the most reactive metals. Potassium literally has a tantrum - it floats, fizzes, produces a lilac flame, and sometimes explodes with crackling sounds before disappearing completely. Sodium's slightly more civilised but still melts into a silvery ball whilst dancing around the surface.
Calcium sinks first (like it's thinking about it) then rises up bubbling away. Magnesium barely bothers - just a few lazy bubbles over ages. Notice the pattern in the equations: Metal + Water → Metal Hydroxide + Hydrogen.
The hydrogen gas produced is what causes all that fizzing and bubbling. Potassium and sodium are so reactive they're stored under oil - otherwise they'd react with moisture in the air before you could even use them!
Safety First: These reactions release heat and produce flammable hydrogen gas - that's why we use safety screens and tongs.
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 steam (water's angry cousin), even the less reactive ones join the party. The key difference? Steam reactions produce metal oxides instead of metal hydroxides - so the equation becomes: Metal + Steam → Metal Oxide + Hydrogen.
Magnesium ribbon burns with that signature bright white light, creating white solid magnesium oxide. Aluminium powder burns too, but it's got a sneaky protective oxide layer that usually keeps it safe from reactions. Zinc powder glows yellow when hot but turns white when it cools down.
Even iron gets involved with steam - the powder glows red-hot and produces black iron oxide. The experimental setup uses mineral wool soaked in water that gets heated to produce steam, which then flows over the heated metal.
Remember: Steam packs more energy than liquid water, so it can persuade less reactive metals to join in the fun.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Displacement reactions are like chemical bullying - a more reactive metal kicks a less reactive one out of its compound and takes its place. These reactions are exothermic, so they'll warm up your test tube nicely.
The displacement table shows the results clearly: put zinc into copper sulphate solution and you'll see a red-brown layer of copper forming whilst the blue colour fades (because the copper ions are leaving the solution). The further apart the metals are on the reactivity series, the faster and more exothermic the reaction becomes.
This concept explains metal extraction methods too. Metals high up in the reactivity series (like aluminium) need electrolysis to extract them because they're so stubborn about giving up their electrons. Less reactive metals can be extracted by reduction - a much gentler approach.
Test Tip: In exams, you'll often get a table showing displacement results - just remember that only more reactive metals can displace less reactive ones!
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.
8
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Quotes from every main character
English LiteratureApp 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