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Chemical Reactions KS3 Revision Notes and Combustion Examples for Year 8 and 9 (PDF Free)
rosie ๐ซ๐งฌ
@nxallsc1ence
Combustion and Thermal Decomposition
This page delves into two important types of chemical reactions: combustion and thermal decomposition, providing crucial Chemical reactions KS3 Worksheet content.
Combustion is the burning of a fuel in oxygen. A fuel is a substance that stores energy in a chemical form.
Definition: Combustion is a chemical reaction where a fuel burns in the presence of oxygen, releasing energy in the form of heat and light.
When a carbon-based fuel undergoes combustion, it produces water and carbon dioxide.
Example: The combustion equation for methane is: methane + oxygen โ carbon dioxide + water
Hydrogen can be used as an alternative fuel, which is more environmentally friendly as it doesn't produce carbon dioxide.
Highlight: The combustion of hydrogen only produces water: hydrogen + oxygen โ water
Thermal decomposition is a reaction where substances are broken down using heat.
Definition: Thermal decomposition is a chemical reaction where a compound breaks down into simpler substances when heated.
An example of thermal decomposition is the breakdown of metal carbonates:
Example: zinc carbonate โ zinc oxide + carbon dioxide
This reaction can be tested by bubbling the produced gas through limewater. If the limewater turns cloudy, it confirms the presence of carbon dioxide.
Vocabulary: Limewater is a solution of calcium hydroxide used to test for the presence of carbon dioxide.
This page provides essential information for understanding combustion and chemical reactions combined science gcse topics, as well as thermal decomposition reaction examples for students.
Chemical Reactions and Conservation of Mass
This page introduces fundamental concepts in chemical reactions, focusing on word equations, conservation of mass, and balanced symbol equations.
Word equations are used to represent chemical reactions, with reactants on the left side of the arrow and products on the right. The arrow signifies the transformation of reactants into new substances.
Definition: A word equation is a way to represent a chemical reaction using the names of substances instead of chemical symbols.
Conservation of mass is a key principle in chemical reactions. It states that the total mass of reactants equals the total mass of products.
Highlight: In a reaction, the amount of each type of atom remains constant, but they are rearranged to form new products.
If it appears that mass has been lost during a reaction, it often means that a gas has been produced and escaped, accounting for the seemingly lost mass.
Balanced symbol equations provide a more detailed representation of chemical reactions. They use symbols from the Periodic Table and show:
- Formulae of reactants and products
- How atoms are rearranged
- Relative amounts of reactants and products
Example: The balanced equation for the formation of water is 2Hโ + Oโ โ 2HโO
Vocabulary: Reactants are the starting substances in a chemical reaction, while products are the substances formed as a result of the reaction.
This page provides essential Chemical reactions KS3 revision material, helping students understand the basics of representing and analyzing chemical reactions.
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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
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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
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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 itโs 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 didnโt even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as Iโm 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 ๐๐๐ฒ๐ค๐โจ๐๐ฎ
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 itโs 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 didnโt even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as Iโm 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 ๐๐๐ฒ๐ค๐โจ๐๐ฎ
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
Chemical Reactions KS3 Revision Notes and Combustion Examples for Year 8 and 9 (PDF Free)
rosie ๐ซ๐งฌ
@nxallsc1ence
Chemical Reactions: A Comprehensive Guide for Year 8 and 9 Students
This guide provides essential Chemical reactions revision notes for year 8 and 9students, covering key concepts such as word equations, conservation of mass, balanced symbol equations, combustion, and... Show more
Combustion and Thermal Decomposition
This page delves into two important types of chemical reactions: combustion and thermal decomposition, providing crucial Chemical reactions KS3 Worksheet content.
Combustion is the burning of a fuel in oxygen. A fuel is a substance that stores energy in a chemical form.
Definition: Combustion is a chemical reaction where a fuel burns in the presence of oxygen, releasing energy in the form of heat and light.
When a carbon-based fuel undergoes combustion, it produces water and carbon dioxide.
Example: The combustion equation for methane is: methane + oxygen โ carbon dioxide + water
Hydrogen can be used as an alternative fuel, which is more environmentally friendly as it doesn't produce carbon dioxide.
Highlight: The combustion of hydrogen only produces water: hydrogen + oxygen โ water
Thermal decomposition is a reaction where substances are broken down using heat.
Definition: Thermal decomposition is a chemical reaction where a compound breaks down into simpler substances when heated.
An example of thermal decomposition is the breakdown of metal carbonates:
Example: zinc carbonate โ zinc oxide + carbon dioxide
This reaction can be tested by bubbling the produced gas through limewater. If the limewater turns cloudy, it confirms the presence of carbon dioxide.
Vocabulary: Limewater is a solution of calcium hydroxide used to test for the presence of carbon dioxide.
This page provides essential information for understanding combustion and chemical reactions combined science gcse topics, as well as thermal decomposition reaction examples for students.
Sign up to see the contentIt's free!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Chemical Reactions and Conservation of Mass
This page introduces fundamental concepts in chemical reactions, focusing on word equations, conservation of mass, and balanced symbol equations.
Word equations are used to represent chemical reactions, with reactants on the left side of the arrow and products on the right. The arrow signifies the transformation of reactants into new substances.
Definition: A word equation is a way to represent a chemical reaction using the names of substances instead of chemical symbols.
Conservation of mass is a key principle in chemical reactions. It states that the total mass of reactants equals the total mass of products.
Highlight: In a reaction, the amount of each type of atom remains constant, but they are rearranged to form new products.
If it appears that mass has been lost during a reaction, it often means that a gas has been produced and escaped, accounting for the seemingly lost mass.
Balanced symbol equations provide a more detailed representation of chemical reactions. They use symbols from the Periodic Table and show:
- Formulae of reactants and products
- How atoms are rearranged
- Relative amounts of reactants and products
Example: The balanced equation for the formation of water is 2Hโ + Oโ โ 2HโO
Vocabulary: Reactants are the starting substances in a chemical reaction, while products are the substances formed as a result of the reaction.
This page provides essential Chemical reactions KS3 revision material, helping students understand the basics of representing and analyzing chemical reactions.
We thought youโd never ask...
What is the Knowunity AI companion?
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.
Where can I download the Knowunity app?
You can download the app from Google Play Store and Apple App Store.
Is Knowunity really free of charge?
That's right! Enjoy free access to study content, connect with fellow students, and get instant help โ all at your fingertips.
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Most popular content: Combustion Reaction
Most popular content in Chemistry
Most popular content
Can't find what you're looking for? Explore other subjects.
Students love us โ and so will you.
4.9/5
App Store
4.8/5
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 itโs 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 didnโt even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as Iโm 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 ๐๐๐ฒ๐ค๐โจ๐๐ฎ
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 itโs 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 didnโt even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as Iโm 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 ๐๐๐ฒ๐ค๐โจ๐๐ฎ
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