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Chemistry
9 Dec 2025
812
4 pages
Zainab @zainab_02839
This document covers key concepts in chemical reaction rates and equilibrium for GCSE Chemistry. It explains how to... Show more
This page continues the discussion on factors affecting rate of reaction surface area and introduces catalysts and a practical experiment.
Surface area is further explained
Catalysts are introduced as a factor that lowers the activation energy, allowing reactions to occur more quickly.
Definition A hypothesis is defined as a proposal that can explain a fact or observation.
The page then outlines the "Disappearing Cross Reaction" practical experiment, which is used to study reaction rates. This experiment involves
Example This practical demonstrates how temperature affects the rate of reaction by varying the concentration of reactants.
The page concludes by discussing potential issues with the experiment, such as subjectivity in determining when the cross disappears, and introduces the concept of reproducible measurements.
This page covers an alternative method for measuring reaction rates by collecting gas, and introduces the concept of reversible reactions and equilibrium.
The gas collection method involves
Highlight This method provides a more objective measure of reaction rate compared to the disappearing cross experiment.
The page then introduces reversible reactions
Definition A reversible reaction is one where the products can react to form the reactants.
Key points about reversible reactions include
The page explains that equilibrium can't be reached in an open system because energy can escape. It also introduces the concepts of equilibrium lying to the left (more reactants) or right (more products).
Vocabulary Le Chatelier's Principle is introduced as the idea that if conditions of a reversible reaction at equilibrium change, the system will try to counteract that change.
This principle is crucial for understanding reversible reactions and dynamic equilibrium GCSE notes questions.
This final page focuses on the factors that affect reversible reactions and their equilibrium positions, which is essential knowledge for reversible reactions GCSE studies.
The main factors discussed are
Temperature
Concentration
Pressure
Example In the reaction N2 + 3H2 ⇌ 2NH3, increasing pressure would favor the formation of ammonia (NH3) as there are fewer molecules on the product side.
These factors illustrate practical applications of Le Chatelier's Principle, showing how equilibrium systems respond to external changes.
Highlight Understanding these factors is crucial for predicting and controlling the outcome of reversible reactions in industrial processes and natural systems.
This knowledge forms the foundation for more advanced studies in chemical equilibrium and kinetics in higher-level chemistry courses.
This page introduces fundamental concepts related to rate of reaction equation GCSE Chemistry. It covers the equation for calculating reaction rates, units used, and key definitions.
The rate of reaction equation is presented as (average) rate of reaction = quantity of products formed (or of reactants used) / time taken
Vocabulary Activation energy is defined as the minimum amount of energy required for a chemical reaction to occur.
Collision theory is explained as the principle that particles must collide with sufficient energy for a reaction to take place.
The page then outlines factors affecting reaction rates
Highlight Understanding these factors is crucial for factors affecting rate of reaction GCSE Chemistry.
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.
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Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore key concepts in reaction kinetics and the properties of hydrocarbons in this comprehensive study resource. Understand the rate of reaction, collision theory, and the significance of carbon compounds as fuels and feedstock. Ideal for GCSE Chemistry revision, this summary covers essential formulas and principles, including activation energy and the characteristics of alkanes and alkenes.
ChemistryExplore the principles of catalysts and collision theory in chemical reactions. This summary covers key concepts such as activation energy, reaction kinetics, and factors affecting reaction rates, including concentration, temperature, and surface area. Ideal for GCSE students seeking to understand how these elements influence chemical processes.
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
Zainab
@zainab_02839
This document covers key concepts in chemical reaction rates and equilibrium for GCSE Chemistry. It explains how to calculate reaction rates, factors affecting reaction speed, and principles of reversible reactions and equilibrium.
• The rate of reaction equation and units... Show more
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Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
This page continues the discussion on factors affecting rate of reaction surface area and introduces catalysts and a practical experiment.
Surface area is further explained:
Catalysts are introduced as a factor that lowers the activation energy, allowing reactions to occur more quickly.
Definition: A hypothesis is defined as a proposal that can explain a fact or observation.
The page then outlines the "Disappearing Cross Reaction" practical experiment, which is used to study reaction rates. This experiment involves:
Example: This practical demonstrates how temperature affects the rate of reaction by varying the concentration of reactants.
The page concludes by discussing potential issues with the experiment, such as subjectivity in determining when the cross disappears, and introduces the concept of reproducible measurements.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
This page covers an alternative method for measuring reaction rates by collecting gas, and introduces the concept of reversible reactions and equilibrium.
The gas collection method involves:
Highlight: This method provides a more objective measure of reaction rate compared to the disappearing cross experiment.
The page then introduces reversible reactions:
Definition: A reversible reaction is one where the products can react to form the reactants.
Key points about reversible reactions include:
The page explains that equilibrium can't be reached in an open system because energy can escape. It also introduces the concepts of equilibrium lying to the left (more reactants) or right (more products).
Vocabulary: Le Chatelier's Principle is introduced as the idea that if conditions of a reversible reaction at equilibrium change, the system will try to counteract that change.
This principle is crucial for understanding reversible reactions and dynamic equilibrium GCSE notes questions.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
This final page focuses on the factors that affect reversible reactions and their equilibrium positions, which is essential knowledge for reversible reactions GCSE studies.
The main factors discussed are:
Temperature:
Concentration:
Pressure:
Example: In the reaction N2 + 3H2 ⇌ 2NH3, increasing pressure would favor the formation of ammonia (NH3) as there are fewer molecules on the product side.
These factors illustrate practical applications of Le Chatelier's Principle, showing how equilibrium systems respond to external changes.
Highlight: Understanding these factors is crucial for predicting and controlling the outcome of reversible reactions in industrial processes and natural systems.
This knowledge forms the foundation for more advanced studies in chemical equilibrium and kinetics in higher-level chemistry courses.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
This page introduces fundamental concepts related to rate of reaction equation GCSE Chemistry. It covers the equation for calculating reaction rates, units used, and key definitions.
The rate of reaction equation is presented as: (average) rate of reaction = quantity of products formed (or of reactants used) / time taken
Vocabulary: Activation energy is defined as the minimum amount of energy required for a chemical reaction to occur.
Collision theory is explained as the principle that particles must collide with sufficient energy for a reaction to take place.
The page then outlines factors affecting reaction rates:
Highlight: Understanding these factors is crucial for factors affecting rate of reaction GCSE Chemistry.
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.
15
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore key concepts in reaction kinetics and the properties of hydrocarbons in this comprehensive study resource. Understand the rate of reaction, collision theory, and the significance of carbon compounds as fuels and feedstock. Ideal for GCSE Chemistry revision, this summary covers essential formulas and principles, including activation energy and the characteristics of alkanes and alkenes.
ChemistryExplore the principles of catalysts and collision theory in chemical reactions. This summary covers key concepts such as activation energy, reaction kinetics, and factors affecting reaction rates, including concentration, temperature, and surface area. Ideal for GCSE students seeking to understand how these elements influence chemical processes.
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