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Chemical bonding is all about how atoms stick together to... Show more







Ever wondered why metals are so good at conducting electricity? It's all down to metallic bonding - one of chemistry's most fascinating concepts.
Metallic bonds form because of electrostatic attraction between positively charged metal ions and a "sea" of delocalised electrons that move freely around them. Think of it like metal atoms swimming in a pool of shared electrons that don't belong to any particular atom.
The strength of metallic bonds depends on the charge of the metal ion - the more positive the charge, the stronger the attraction and the tougher the bond. Pure metals are actually quite soft because their atoms are all the same size, so layers can slide over each other easily.
Alloys are mixtures of two or more metals that solve this problem. They're much harder than pure metals because the different-sized atoms disrupt the neat layers, preventing them from sliding past each other.
Quick Tip: Remember that delocalised electrons are the key to understanding most metallic properties!

Ionic bonding happens when metals meet non-metals, and it's basically atomic give-and-take at its finest.
Here's how it works: metals transfer electrons to non-metals, creating charged particles called ions. Take sodium fluoride - sodium gives up its outer electron to fluorine, making Na⁺ and F⁻ ions. Both atoms become stable, and everyone's happy!
The magic happens through electrostatic attraction between these oppositely charged ions. It's like tiny magnets - positive attracts negative, forming strong ionic compounds.
Top tip for exams: Ionic bonding always involves at least one metal and one non-metal. Use the charge cheat sheet to work out ion charges - Group 1 metals form 1⁺ ions, Group 2 form 2⁺ ions, and so on.
Memory Hook: Think "ionic = transfer" - electrons move from one atom to another!

Covalent bonding is all about sharing, and it only happens between non-metal atoms who've decided to pool their electrons together.
Diatomic molecules like Cl₂ are perfect examples - two chlorine atoms share electrons to become stable. You'll see this in loads of common molecules like water (H₂O), carbon dioxide (CO₂), and ammonia (NH₃).
There are several ways to represent covalent bonds. Dot and cross diagrams show the electronic structure clearly, whilst displayed formulas use simple lines. Ball and stick models are brilliant because they show the actual 3D shape of molecules.
The key thing to remember is that electrons are shared, not transferred like in ionic bonding. This sharing creates strong bonds within molecules, but the forces between separate molecules are much weaker.
Exam Success: Practice drawing dot and cross diagrams - they're exam favourites and really help you understand what's happening!

Understanding melting and boiling points is crucial for predicting how different materials behave when heated.
Metallic substances have very high melting and boiling points because those delocalised electrons create incredibly strong bonds. You need loads of energy to break apart that sea of electrons and separate the metal ions.
Ionic compounds also have high melting and boiling points. The strong electrostatic attraction between positive and negative ions in the giant ionic lattice takes serious energy to overcome.
Covalent substances are the odd ones out. Whilst the bonds within molecules are strong, the intermolecular forces between separate molecules are weak. This means simple molecular substances have low melting and boiling points - you don't need much energy to separate the molecules from each other.
Key Insight: It's not about breaking the bonds within molecules, but about separating whole molecules from each other!

Malleability explains why you can bend metals without snapping them, but this property changes dramatically in alloys.
In pure metals, atoms are all the same size, so layers can slide smoothly over each other when force is applied. Alloys like steel, brass, and bronze are much harder because different-sized atoms disrupt this sliding action, making them more brittle.
Solubility is all about polar molecules, especially water. Water is polar because it has both partial positive (δ⁺) and partial negative (δ⁻) charges on different parts of the molecule.
When giant ionic substances meet water, the polar water molecules attract and separate the ions, causing the solid to dissolve. At GCSE level, remember that only giant ionic substances are soluble in water - compounds like CaCl₂, MgO, and NaOH all dissolve because they're ionic.
Water Wisdom: If it's ionic, it's likely soluble - water's polar nature is the key!

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Anna
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Best app on earth! no words because it’s too good
Thomas R
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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
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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
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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!
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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.
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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
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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
Chemical bonding is all about how atoms stick together to form the substances around you - from the metal in your phone to the salt on your chips. There are three main types of bonding that explain why materials behave... Show more

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Ever wondered why metals are so good at conducting electricity? It's all down to metallic bonding - one of chemistry's most fascinating concepts.
Metallic bonds form because of electrostatic attraction between positively charged metal ions and a "sea" of delocalised electrons that move freely around them. Think of it like metal atoms swimming in a pool of shared electrons that don't belong to any particular atom.
The strength of metallic bonds depends on the charge of the metal ion - the more positive the charge, the stronger the attraction and the tougher the bond. Pure metals are actually quite soft because their atoms are all the same size, so layers can slide over each other easily.
Alloys are mixtures of two or more metals that solve this problem. They're much harder than pure metals because the different-sized atoms disrupt the neat layers, preventing them from sliding past each other.
Quick Tip: Remember that delocalised electrons are the key to understanding most metallic properties!

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Ionic bonding happens when metals meet non-metals, and it's basically atomic give-and-take at its finest.
Here's how it works: metals transfer electrons to non-metals, creating charged particles called ions. Take sodium fluoride - sodium gives up its outer electron to fluorine, making Na⁺ and F⁻ ions. Both atoms become stable, and everyone's happy!
The magic happens through electrostatic attraction between these oppositely charged ions. It's like tiny magnets - positive attracts negative, forming strong ionic compounds.
Top tip for exams: Ionic bonding always involves at least one metal and one non-metal. Use the charge cheat sheet to work out ion charges - Group 1 metals form 1⁺ ions, Group 2 form 2⁺ ions, and so on.
Memory Hook: Think "ionic = transfer" - electrons move from one atom to another!

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Covalent bonding is all about sharing, and it only happens between non-metal atoms who've decided to pool their electrons together.
Diatomic molecules like Cl₂ are perfect examples - two chlorine atoms share electrons to become stable. You'll see this in loads of common molecules like water (H₂O), carbon dioxide (CO₂), and ammonia (NH₃).
There are several ways to represent covalent bonds. Dot and cross diagrams show the electronic structure clearly, whilst displayed formulas use simple lines. Ball and stick models are brilliant because they show the actual 3D shape of molecules.
The key thing to remember is that electrons are shared, not transferred like in ionic bonding. This sharing creates strong bonds within molecules, but the forces between separate molecules are much weaker.
Exam Success: Practice drawing dot and cross diagrams - they're exam favourites and really help you understand what's happening!

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Understanding melting and boiling points is crucial for predicting how different materials behave when heated.
Metallic substances have very high melting and boiling points because those delocalised electrons create incredibly strong bonds. You need loads of energy to break apart that sea of electrons and separate the metal ions.
Ionic compounds also have high melting and boiling points. The strong electrostatic attraction between positive and negative ions in the giant ionic lattice takes serious energy to overcome.
Covalent substances are the odd ones out. Whilst the bonds within molecules are strong, the intermolecular forces between separate molecules are weak. This means simple molecular substances have low melting and boiling points - you don't need much energy to separate the molecules from each other.
Key Insight: It's not about breaking the bonds within molecules, but about separating whole molecules from each other!

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Malleability explains why you can bend metals without snapping them, but this property changes dramatically in alloys.
In pure metals, atoms are all the same size, so layers can slide smoothly over each other when force is applied. Alloys like steel, brass, and bronze are much harder because different-sized atoms disrupt this sliding action, making them more brittle.
Solubility is all about polar molecules, especially water. Water is polar because it has both partial positive (δ⁺) and partial negative (δ⁻) charges on different parts of the molecule.
When giant ionic substances meet water, the polar water molecules attract and separate the ions, causing the solid to dissolve. At GCSE level, remember that only giant ionic substances are soluble in water - compounds like CaCl₂, MgO, and NaOH all dissolve because they're ionic.
Water Wisdom: If it's ionic, it's likely soluble - water's polar nature is the key!

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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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Explore the key differences between metals and non-metals in this GCSE Chemistry summary. Understand properties such as conductivity, malleability, and reactivity, along with the behavior of metal and non-metal atoms in terms of electron transfer and ion formation. Ideal for exam preparation and quick revision.
Explore the key concepts of the Periodic Table, including the properties of metals and non-metals, reactivity trends in alkali metals and halogens, and the significance of atomic structure. This summary is tailored for Year 10 Chemistry students, providing a clear understanding of periodic trends and electronic configurations.
Explore the properties and classifications of elements in the periodic table, including noble gases, alkali metals, halogens, and transition metals. This summary covers atomic structure, reactivity, and trends in melting and boiling points, providing essential knowledge for chemistry students. Ideal for exam preparation and understanding elemental behavior.
Explore the structure and organization of the Periodic Table, including the classification of elements into metals and non-metals, their electronic structures, and the significance of atomic number and atomic weight. This summary is essential for GCSE Chemistry students seeking to grasp the foundational concepts of chemical elements and their properties.
Explore the key characteristics of metallic bonding, including high melting points, electrical conductivity, malleability, and ductility. This summary covers the structure of metals, the role of delocalized electrons, and how these properties arise from the lattice arrangement of metal atoms. Ideal for GCSE Chemistry students seeking to understand the fundamentals of metallic solids.
Explore the key concepts of the Periodic Table, including metals, non-metals, alkali and alkaline earth metals, and periodic trends. This summary provides a clear overview for GCSE chemistry students, highlighting atomic structure, reactivity, and the properties of elements across different groups.
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The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user