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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
26 Nov 2025
550
4 pages
Emily ๐ @em_redhead
Year 8 Acids and Alkalis: A comprehensive guide to understanding the fundamental concepts of acids and alkalis,... Show more
The pH Scale and Indicators
This page delves into the pH scale and the use of indicators to test the acidity or alkalinity of substances. It provides a comprehensive overview of how the pH scale works and its importance in chemistry.
The pH scale ranges from 0 to 14, with acids having a pH below 7, neutral solutions at pH 7, and alkalis above 7. The page explains how the strength of an acid or alkali corresponds to its position on the pH scale.
Various indicators are introduced, including litmus paper and universal indicator. These tools change color when exposed to acidic or alkaline solutions, allowing for the determination of a substance's pH.
Definition An indicator is a substance that changes color when added to acidic or alkaline solutions, helping to determine their pH.
Example Litmus paper turns red in acidic solutions and blue in alkaline solutions, while universal indicator displays a range of colors corresponding to different pH levels.
Highlight Natural substances like red cabbage, tea, and rose petals can also serve as pH indicators.
Vocabulary Universal indicator is a type of indicator that shows many different color changes across the pH scale, from red for strongly acidic solutions to dark purple for strongly alkaline solutions.
Neutralization Reactions
This page focuses on neutralization reactions, a crucial concept in the study of acids and alkalis. It explains how these reactions occur and their importance in various contexts.
Neutralization is the process where an acid and an alkali react to form a salt and water. The page provides a general equation for neutralization reactions and specific examples using different acids and alkalis.
The concept of titration is introduced as a method for carrying out accurate neutralization reactions in a laboratory setting. The page also highlights the relevance of neutralization reactions in everyday life, such as in the digestive system and in treating indigestion.
Definition Neutralization is a chemical reaction where an acid and an alkali combine to form a salt and water, resulting in a neutral solution.
Example The neutralization of hydrochloric acid with sodium hydroxide produces sodium chloride (table salt) and water.
Highlight Neutralization reactions play a crucial role in the human body, particularly in the digestive system. Antacids, which contain alkalis, are used to neutralize excess stomach acid and relieve indigestion.
Vocabulary Titration is a laboratory technique used to carry out accurate neutralization reactions by carefully adding one solution to another until the reaction is complete.
Making Salts
This final page outlines the process of making salts through the reaction of metal oxides with acids. It provides a step-by-step guide to this important chemical procedure.
The salt-making process is divided into three main steps reacting the metal oxide with the acid, filtering to remove excess solid, and evaporating water to form crystals. Each step is explained in detail, with accompanying diagrams to illustrate the equipment and setup used.
The page emphasizes the importance of using excess solid to ensure complete neutralization of the acid and the technique of slow evaporation to produce larger crystals.
Definition Salt formation is the process of creating a salt through the reaction of an acid with a metal oxide, followed by filtration and evaporation.
Example The reaction of copper oxide with sulfuric acid produces copper sulfate salt and water.
Highlight Slow evaporation at room temperature is used to produce larger salt crystals, which is an important technique in crystal formation.
Vocabulary Filtration is the process of separating solid particles from a liquid using a filter paper or other porous material.
Acids and Alkalis Fundamental Concepts
This page introduces the basic concepts of acids and alkalis, their definitions, and examples. It also covers hazard symbols associated with these substances.
Acids are substances with a pH lower than 7, while alkalis are soluble substances with a pH higher than 7. Examples of acids include hydrochloric acid and citric acid, while examples of alkalis include sodium hydroxide and toothpaste.
The page explains the concept of concentration in acids and how it relates to their strength and potential hazards. It also introduces important hazard symbols used to indicate the level and type of danger associated with these substances.
Definition An acid is a substance with a pH lower than 7, while an alkali is a soluble substance with a pH higher than 7.
Example Hydrochloric acid and citric acid are examples of acids, while sodium hydroxide and toothpaste are examples of alkalis.
Highlight Concentration is a measure of the number of particles in a given volume. Strong acids can be very concentrated and dangerous, but they can be diluted with water to make them less hazardous.
Vocabulary Hazard symbols are used to show the level and type of danger associated with a substance. Common symbols include corrosive, toxic, and irritant.
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 โ all at your fingertips.
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Transform this note into: โ 50+ Practice Questions โ Interactive Flashcards โ Full Mock Exam โ Essay Outlines
Explore the step-by-step process of acid-base titrations, including essential techniques for accurate measurements and color change observations. This detailed guide covers the titration method, the significance of the equivalence point, and tips for achieving concordant results. Ideal for chemistry students preparing for exams.
ChemistryExplore the pH scale, including definitions and examples of acids, alkalis, and neutral substances. This summary covers key concepts such as acid-base reactions and neutralization processes, providing essential insights for chemistry students.
ChemistryExplore the essential concepts of acids and alkalis, including their properties, everyday examples, and the process of neutralisation. This summary covers laboratory acids and alkalis, pH testing methods, and practical applications such as antacids and soil treatment. Ideal for chemistry students seeking a clear understanding of acid-base reactions.
ChemistryExplore the fundamentals of acid-base reactions, including neutralization, titration techniques, and the reactivity of metals. This summary covers key concepts such as making salts, pH indicators, and the differences between strong and weak acids. Ideal for AQA GCSE Chemistry revision.
ChemistryExplore the fundamentals of acids and bases, including the pH scale, neutralization reactions, and the formation of salts. This summary covers key concepts such as the effects of metal and non-metal oxides on pH, common acids and alkalis, and the implications of acid rain. Ideal for chemistry students preparing for exams.
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 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
Emily ๐
@em_redhead
Year 8 Acids and Alkalis: A comprehensive guide to understanding the fundamental concepts of acids and alkalis, including their properties, pH scale, indicators, neutralization reactions, and salt formation. This summary sheet covers essential information for GCSE-level chemistry, providing clear... Show more
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The pH Scale and Indicators
This page delves into the pH scale and the use of indicators to test the acidity or alkalinity of substances. It provides a comprehensive overview of how the pH scale works and its importance in chemistry.
The pH scale ranges from 0 to 14, with acids having a pH below 7, neutral solutions at pH 7, and alkalis above 7. The page explains how the strength of an acid or alkali corresponds to its position on the pH scale.
Various indicators are introduced, including litmus paper and universal indicator. These tools change color when exposed to acidic or alkaline solutions, allowing for the determination of a substance's pH.
Definition: An indicator is a substance that changes color when added to acidic or alkaline solutions, helping to determine their pH.
Example: Litmus paper turns red in acidic solutions and blue in alkaline solutions, while universal indicator displays a range of colors corresponding to different pH levels.
Highlight: Natural substances like red cabbage, tea, and rose petals can also serve as pH indicators.
Vocabulary: Universal indicator is a type of indicator that shows many different color changes across the pH scale, from red for strongly acidic solutions to dark purple for strongly alkaline solutions.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Neutralization Reactions
This page focuses on neutralization reactions, a crucial concept in the study of acids and alkalis. It explains how these reactions occur and their importance in various contexts.
Neutralization is the process where an acid and an alkali react to form a salt and water. The page provides a general equation for neutralization reactions and specific examples using different acids and alkalis.
The concept of titration is introduced as a method for carrying out accurate neutralization reactions in a laboratory setting. The page also highlights the relevance of neutralization reactions in everyday life, such as in the digestive system and in treating indigestion.
Definition: Neutralization is a chemical reaction where an acid and an alkali combine to form a salt and water, resulting in a neutral solution.
Example: The neutralization of hydrochloric acid with sodium hydroxide produces sodium chloride (table salt) and water.
Highlight: Neutralization reactions play a crucial role in the human body, particularly in the digestive system. Antacids, which contain alkalis, are used to neutralize excess stomach acid and relieve indigestion.
Vocabulary: Titration is a laboratory technique used to carry out accurate neutralization reactions by carefully adding one solution to another until the reaction is complete.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Making Salts
This final page outlines the process of making salts through the reaction of metal oxides with acids. It provides a step-by-step guide to this important chemical procedure.
The salt-making process is divided into three main steps: reacting the metal oxide with the acid, filtering to remove excess solid, and evaporating water to form crystals. Each step is explained in detail, with accompanying diagrams to illustrate the equipment and setup used.
The page emphasizes the importance of using excess solid to ensure complete neutralization of the acid and the technique of slow evaporation to produce larger crystals.
Definition: Salt formation is the process of creating a salt through the reaction of an acid with a metal oxide, followed by filtration and evaporation.
Example: The reaction of copper oxide with sulfuric acid produces copper sulfate salt and water.
Highlight: Slow evaporation at room temperature is used to produce larger salt crystals, which is an important technique in crystal formation.
Vocabulary: Filtration is the process of separating solid particles from a liquid using a filter paper or other porous material.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Acids and Alkalis: Fundamental Concepts
This page introduces the basic concepts of acids and alkalis, their definitions, and examples. It also covers hazard symbols associated with these substances.
Acids are substances with a pH lower than 7, while alkalis are soluble substances with a pH higher than 7. Examples of acids include hydrochloric acid and citric acid, while examples of alkalis include sodium hydroxide and toothpaste.
The page explains the concept of concentration in acids and how it relates to their strength and potential hazards. It also introduces important hazard symbols used to indicate the level and type of danger associated with these substances.
Definition: An acid is a substance with a pH lower than 7, while an alkali is a soluble substance with a pH higher than 7.
Example: Hydrochloric acid and citric acid are examples of acids, while sodium hydroxide and toothpaste are examples of alkalis.
Highlight: Concentration is a measure of the number of particles in a given volume. Strong acids can be very concentrated and dangerous, but they can be diluted with water to make them less hazardous.
Vocabulary: Hazard symbols are used to show the level and type of danger associated with a substance. Common symbols include corrosive, toxic, and irritant.
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 โ all at your fingertips.
60
Smart Tools NEW
Transform this note into: โ 50+ Practice Questions โ Interactive Flashcards โ Full Mock Exam โ Essay Outlines
Explore the step-by-step process of acid-base titrations, including essential techniques for accurate measurements and color change observations. This detailed guide covers the titration method, the significance of the equivalence point, and tips for achieving concordant results. Ideal for chemistry students preparing for exams.
ChemistryExplore the pH scale, including definitions and examples of acids, alkalis, and neutral substances. This summary covers key concepts such as acid-base reactions and neutralization processes, providing essential insights for chemistry students.
ChemistryExplore the essential concepts of acids and alkalis, including their properties, everyday examples, and the process of neutralisation. This summary covers laboratory acids and alkalis, pH testing methods, and practical applications such as antacids and soil treatment. Ideal for chemistry students seeking a clear understanding of acid-base reactions.
ChemistryExplore the fundamentals of acid-base reactions, including neutralization, titration techniques, and the reactivity of metals. This summary covers key concepts such as making salts, pH indicators, and the differences between strong and weak acids. Ideal for AQA GCSE Chemistry revision.
ChemistryExplore the fundamentals of acids and bases, including the pH scale, neutralization reactions, and the formation of salts. This summary covers key concepts such as the effects of metal and non-metal oxides on pH, common acids and alkalis, and the implications of acid rain. Ideal for chemistry students preparing for exams.
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 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
