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Britain & the wider world: 1745 -1901
1l the quest for political stability: germany, 1871-1991
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Inter-war germany
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2d religious conflict and the church in england, c1529-c1570
2o democracy and nazism: germany, 1918-1945
1f industrialisation and the people: britain, c1783-1885
1c the tudors: england, 1485-1603
2m wars and welfare: britain in transition, 1906-1957
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2s the making of modern britain, 1951-2007
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Chemistry
2 Dec 2025
113
4 pages
Mill xx @millie1515
Ever wondered why salt has such a high melting point or how your phone battery works? It's all... Show more
Think of ionic compounds as tiny magnets that can't let go of each other. All ionic compounds contain charged particles called ions - some positive, some negative. When oppositely charged ions meet, they form an incredibly strong attraction called an ionic bond.
These ions don't just randomly stick together though. They arrange themselves in a neat, repeating pattern called a giant ionic structure, which is why you see crystals forming. The electrostatic forces holding them together are so strong that it takes loads of energy to pull them apart.
Quick Tip Remember that opposite charges attract - just like how a positive sodium ion (Na⁺) will always grab onto a negative chloride ion (Cl⁻) to make salt!
Here's something mental - magnesium oxide melts at 2852°C! That's hot enough to melt copper. Ionic compounds have ridiculously high melting and boiling points because those electrostatic forces between ions are absolutely massive.
The bigger the charge on the ion, the stronger the attraction. This is why magnesium oxide (with Mg²⁺ and O²⁻ ions) melts at nearly 3000°C, whilst sodium chloride (Na⁺ and Cl⁻) 'only' melts at about 800°C. You need loads of energy to force these charged particles apart.
Think of it like trying to separate two really powerful magnets - the stronger they are, the more effort you need to pull them apart.
Real-World Connection This is why salt doesn't melt in your oven, but ice cubes do - ionic bonds are way stronger than the forces holding water molecules together!
Here's where it gets interesting - ionic compounds are brilliant at conducting electricity, but only under certain conditions. They'll conduct when they're molten (melted) or dissolved in water (aqueous), but they're useless when solid.
Electrical conductivity happens because you need two things charged particles (which ions definitely are) and the freedom to move around. In a solid, the ions are locked in place like prisoners in a crystal structure. But melt them or dissolve them, and suddenly those ions can move freely and carry an electric current.
This is exactly how your phone battery works - ions moving around in a liquid to carry electrical charge from one place to another.
Memory Trick Solid ionic compounds are like a traffic jam - the cars (ions) are there but can't move. Molten or dissolved compounds are like an open motorway - traffic flows freely!
When ionic compounds conduct electricity, it's like a perfectly choreographed dance. The positively charged cations always head towards the negative cathode, whilst the negatively charged anions march towards the positive anode.
This movement isn't random - opposites attract, so positive ions naturally move towards negative electrodes and vice versa. It's this organised movement of charged particles that creates an electric current.
Understanding this behaviour is crucial for loads of topics you'll cover later, from batteries to metal extraction. The key thing to remember is that ions only move when they're free to do so - never when they're stuck in a solid structure.
Exam Tip Remember the phrase "PANiC" - Positive Anode, Negative is Cathode. It'll save you marks when identifying which electrode is which!
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 the three primary states of matter—solids, liquids, and gases—in this concise summary. Understand key concepts such as particle arrangement, physical changes, and the kinetic theory. Ideal for GCSE chemistry revision, this resource highlights the properties and behaviors of each state, including phase changes and the less common aqueous state.
ChemistryExplore the key concepts of phase transitions in matter, including sublimation, melting, boiling, evaporation, and condensation. This summary covers the characteristics of solids, liquids, and gases, their unique properties, and the specific temperatures at which phase changes occur. Ideal for GCSE Chemistry students seeking to grasp the fundamentals of states of matter.
ChemistryExplore the key concepts of ionic, covalent, and metallic bonding in this comprehensive study note. Includes detailed diagrams, explanations of bonding types, and typical exam questions to enhance your understanding of chemical bonding and properties. Ideal for GCSE Chemistry students.
ChemistryExplore the key concepts of bonding and structure in chemistry, including ionic, covalent, and metallic bonding, as well as the properties of giant covalent structures and nanoparticles. This summary covers essential topics for GCSE students, focusing on particle theory, intermolecular forces, and the unique characteristics of various molecular structures. Ideal for active recall and exam preparation.
ChemistryExplore the evolution of atomic models from John Dalton's solid spheres to Rutherford's nuclear atom and Bohr's electron shells. This summary highlights key experiments and theories that shaped our understanding of atomic structure, making it essential for students studying chemistry and physics.
ChemistryExplore the fundamentals of chemical bonding, including ionic, covalent, and metallic structures. This summary covers the properties of solids, liquids, and gases, the formation of compounds, and the significance of giant covalent structures and nanoparticles. Ideal for AQA GCSE Chemistry Higher students seeking to understand the intricacies of molecular interactions and material properties.
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
Mill xx
@millie1515
Ever wondered why salt has such a high melting point or how your phone battery works? It's all down to ionic compounds - substances made of charged particles that stick together with incredibly strong forces. Understanding how these compounds behave... Show more
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Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Think of ionic compounds as tiny magnets that can't let go of each other. All ionic compounds contain charged particles called ions - some positive, some negative. When oppositely charged ions meet, they form an incredibly strong attraction called an ionic bond.
These ions don't just randomly stick together though. They arrange themselves in a neat, repeating pattern called a giant ionic structure, which is why you see crystals forming. The electrostatic forces holding them together are so strong that it takes loads of energy to pull them apart.
Quick Tip: Remember that opposite charges attract - just like how a positive sodium ion (Na⁺) will always grab onto a negative chloride ion (Cl⁻) to make salt!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Here's something mental - magnesium oxide melts at 2852°C! That's hot enough to melt copper. Ionic compounds have ridiculously high melting and boiling points because those electrostatic forces between ions are absolutely massive.
The bigger the charge on the ion, the stronger the attraction. This is why magnesium oxide (with Mg²⁺ and O²⁻ ions) melts at nearly 3000°C, whilst sodium chloride (Na⁺ and Cl⁻) 'only' melts at about 800°C. You need loads of energy to force these charged particles apart.
Think of it like trying to separate two really powerful magnets - the stronger they are, the more effort you need to pull them apart.
Real-World Connection: This is why salt doesn't melt in your oven, but ice cubes do - ionic bonds are way stronger than the forces holding water molecules together!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Here's where it gets interesting - ionic compounds are brilliant at conducting electricity, but only under certain conditions. They'll conduct when they're molten (melted) or dissolved in water (aqueous), but they're useless when solid.
Electrical conductivity happens because you need two things: charged particles (which ions definitely are) and the freedom to move around. In a solid, the ions are locked in place like prisoners in a crystal structure. But melt them or dissolve them, and suddenly those ions can move freely and carry an electric current.
This is exactly how your phone battery works - ions moving around in a liquid to carry electrical charge from one place to another.
Memory Trick: Solid ionic compounds are like a traffic jam - the cars (ions) are there but can't move. Molten or dissolved compounds are like an open motorway - traffic flows freely!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
When ionic compounds conduct electricity, it's like a perfectly choreographed dance. The positively charged cations always head towards the negative cathode, whilst the negatively charged anions march towards the positive anode.
This movement isn't random - opposites attract, so positive ions naturally move towards negative electrodes and vice versa. It's this organised movement of charged particles that creates an electric current.
Understanding this behaviour is crucial for loads of topics you'll cover later, from batteries to metal extraction. The key thing to remember is that ions only move when they're free to do so - never when they're stuck in a solid structure.
Exam Tip: Remember the phrase "PANiC" - Positive Anode, Negative is Cathode. It'll save you marks when identifying which electrode is which!
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.
0
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore the three primary states of matter—solids, liquids, and gases—in this concise summary. Understand key concepts such as particle arrangement, physical changes, and the kinetic theory. Ideal for GCSE chemistry revision, this resource highlights the properties and behaviors of each state, including phase changes and the less common aqueous state.
ChemistryExplore the key concepts of phase transitions in matter, including sublimation, melting, boiling, evaporation, and condensation. This summary covers the characteristics of solids, liquids, and gases, their unique properties, and the specific temperatures at which phase changes occur. Ideal for GCSE Chemistry students seeking to grasp the fundamentals of states of matter.
ChemistryExplore the key concepts of ionic, covalent, and metallic bonding in this comprehensive study note. Includes detailed diagrams, explanations of bonding types, and typical exam questions to enhance your understanding of chemical bonding and properties. Ideal for GCSE Chemistry students.
ChemistryExplore the key concepts of bonding and structure in chemistry, including ionic, covalent, and metallic bonding, as well as the properties of giant covalent structures and nanoparticles. This summary covers essential topics for GCSE students, focusing on particle theory, intermolecular forces, and the unique characteristics of various molecular structures. Ideal for active recall and exam preparation.
ChemistryExplore the evolution of atomic models from John Dalton's solid spheres to Rutherford's nuclear atom and Bohr's electron shells. This summary highlights key experiments and theories that shaped our understanding of atomic structure, making it essential for students studying chemistry and physics.
ChemistryExplore the fundamentals of chemical bonding, including ionic, covalent, and metallic structures. This summary covers the properties of solids, liquids, and gases, the formation of compounds, and the significance of giant covalent structures and nanoparticles. Ideal for AQA GCSE Chemistry Higher students seeking to understand the intricacies of molecular interactions and material properties.
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