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0
J
Jessica Plane
13/12/2025
Chemistry
Chemistry: topic 2
111
•
13 Dec 2025
•
Understanding Chemistry: Structure and Bonding
J
Jessica Plane
@essicalane_jeu6oyvga
1 / 10
Structure and Bonding Overview
Understanding how atoms bond together is crucial for explaining why materials behave so differently. Whether it's why salt dissolves in water or why metals conduct electricity, it all comes down to bonding types.
The three main types of bonding are ionic , covalent , and metallic (metals with metals). Each creates substances with totally different properties that affect how we use them in everyday life.
Quick Tip: Remember the bonding triangle - ionic , covalent , metallic !
Simple Molecular Substances
Simple molecular substances are formed when non-metals bond covalently to create small, separate molecules. Think of hydrogen gas (H₂), water (H₂O), or methane (CH₄) - these are all simple molecules held together by strong covalent bonds within each molecule.
The key thing to remember is that whilst the bonds inside each molecule are strong, the forces between different molecules are incredibly weak. This is why these substances have low boiling points and are often liquids or gases at room temperature.
They also don't conduct electricity because the molecules aren't charged - there are no free electrons or ions to carry electrical current through the substance.
Remember: Strong bonds inside molecules, weak forces between molecules = low boiling points!
Ionic Bonding
Ionic bonding happens when metals meet non-metals, and it's all about electron transfer. Metals lose electrons to become positive ions, whilst non-metals gain electrons to become negative ions .
The magic happens because of electrostatic attraction - opposite charges attract powerfully. When sodium (Na) loses an electron and fluorine (F) gains one, you get Na⁺ and F⁻ ions that stick together strongly.
For example, in magnesium oxide (MgO), magnesium loses 2 electrons to become Mg²⁺, whilst oxygen gains 2 electrons to become O²⁻. The 2+ and 2- charges create a very strong attraction.
Key Point: Metal atoms lose electrons (become positive), non-metal atoms gain electrons (become negative)!
Metallic Bonding
Metallic bonding explains why metals are so useful - it's like atoms sharing a 'sea' of electrons! Metal atoms arrange in a giant regular structure where the outer electrons become delocalised, meaning they're free to move around.
This creates an electrostatic attraction between the positive metal ions and the 'sea' of negative delocalised electrons. It's these mobile electrons that make metals such good electrical and thermal conductors - they can carry charge and energy.
Metals also have high melting points because you need lots of energy to break these strong metallic bonds. Plus, they're soft and malleable because the layers of atoms can slide over each other without breaking bonds.
Think of it: Delocalised electrons are like a mobile phone network - they can move freely to conduct electricity anywhere in the metal!
Alloys and Metallic Properties
Alloys are mixtures of metals (or metals with carbon) that are deliberately made harder than pure metals. When you add different-sized atoms to a pure metal, they disrupt the regular pattern and stop the layers from sliding over each other easily.
This is why steel is much harder than pure iron, and why bronze was so revolutionary in ancient times. The added elements act like 'speed bumps' in the metallic structure.
Pure metals are actually quite soft because their atoms are all the same size, so layers can slide past each other smoothly. Alloys prevent this sliding, making them perfect for construction and tools.
Real-world connection: Your bike frame is probably made from an aluminium alloy - pure aluminium would be too soft!
Covalent Bonding Basics
Covalent bonding occurs between non-metals that need to gain electrons to become stable. Instead of transferring electrons (like ionic bonding), atoms share electrons to fill their outer shells.
There are four ways to show covalent bonds: molecular formulae (like NH₃), dot-and-cross diagrams, ball-and-stick models, and displayed formulae . Each method shows different information about the molecule's structure.
You can have single bonds (one pair of shared electrons), double bonds (two pairs, like O₂), or triple bonds (three pairs, like N₂). The more pairs shared, the stronger the bond between those atoms.
Memory trick: Covalent = 'co-valent' = sharing valence (outer) electrons cooperatively!
Giant Covalent Structures
Giant covalent structures are like massive 3D puzzles where millions of atoms are joined by covalent bonds. The three allotropes of carbon - diamond, graphite, and graphene - show how the same element can have completely different properties.
Diamond has four covalent bonds per carbon atom, creating an incredibly hard, rigid network. Graphite has three bonds per carbon, forming layers that can slide over each other, making it soft and slippery (perfect for pencils!).
Graphene is essentially one layer of graphite - it's incredibly strong yet thin and light. All three have high melting points because you need to break many covalent bonds to melt them.
Amazing fact: Graphite conducts electricity because it has delocalised electrons between layers, but diamond doesn't because all electrons are locked in bonds!
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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.
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Xander S
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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
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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
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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
Understanding Chemistry: Structure and Bonding
J
Jessica Plane
@essicalane_jeu6oyvga
Structure and bonding is all about understanding how atoms stick together to form different materials - from the water you drink to the metal in your phone. There are three main types of bonding that create completely different properties in... Show more
Structure and Bonding Overview
Understanding how atoms bond together is crucial for explaining why materials behave so differently. Whether it's why salt dissolves in water or why metals conduct electricity, it all comes down to bonding types.
The three main types of bonding are ionic , covalent , and metallic (metals with metals). Each creates substances with totally different properties that affect how we use them in everyday life.
Quick Tip: Remember the bonding triangle - ionic , covalent , metallic !
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Simple Molecular Substances
Simple molecular substances are formed when non-metals bond covalently to create small, separate molecules. Think of hydrogen gas (H₂), water (H₂O), or methane (CH₄) - these are all simple molecules held together by strong covalent bonds within each molecule.
The key thing to remember is that whilst the bonds inside each molecule are strong, the forces between different molecules are incredibly weak. This is why these substances have low boiling points and are often liquids or gases at room temperature.
They also don't conduct electricity because the molecules aren't charged - there are no free electrons or ions to carry electrical current through the substance.
Remember: Strong bonds inside molecules, weak forces between molecules = low boiling points!
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Ionic Bonding
Ionic bonding happens when metals meet non-metals, and it's all about electron transfer. Metals lose electrons to become positive ions, whilst non-metals gain electrons to become negative ions .
The magic happens because of electrostatic attraction - opposite charges attract powerfully. When sodium (Na) loses an electron and fluorine (F) gains one, you get Na⁺ and F⁻ ions that stick together strongly.
For example, in magnesium oxide (MgO), magnesium loses 2 electrons to become Mg²⁺, whilst oxygen gains 2 electrons to become O²⁻. The 2+ and 2- charges create a very strong attraction.
Key Point: Metal atoms lose electrons (become positive), non-metal atoms gain electrons (become negative)!
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Metallic Bonding
Metallic bonding explains why metals are so useful - it's like atoms sharing a 'sea' of electrons! Metal atoms arrange in a giant regular structure where the outer electrons become delocalised, meaning they're free to move around.
This creates an electrostatic attraction between the positive metal ions and the 'sea' of negative delocalised electrons. It's these mobile electrons that make metals such good electrical and thermal conductors - they can carry charge and energy.
Metals also have high melting points because you need lots of energy to break these strong metallic bonds. Plus, they're soft and malleable because the layers of atoms can slide over each other without breaking bonds.
Think of it: Delocalised electrons are like a mobile phone network - they can move freely to conduct electricity anywhere in the metal!
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Alloys and Metallic Properties
Alloys are mixtures of metals (or metals with carbon) that are deliberately made harder than pure metals. When you add different-sized atoms to a pure metal, they disrupt the regular pattern and stop the layers from sliding over each other easily.
This is why steel is much harder than pure iron, and why bronze was so revolutionary in ancient times. The added elements act like 'speed bumps' in the metallic structure.
Pure metals are actually quite soft because their atoms are all the same size, so layers can slide past each other smoothly. Alloys prevent this sliding, making them perfect for construction and tools.
Real-world connection: Your bike frame is probably made from an aluminium alloy - pure aluminium would be too soft!
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Covalent Bonding Basics
Covalent bonding occurs between non-metals that need to gain electrons to become stable. Instead of transferring electrons (like ionic bonding), atoms share electrons to fill their outer shells.
There are four ways to show covalent bonds: molecular formulae (like NH₃), dot-and-cross diagrams, ball-and-stick models, and displayed formulae . Each method shows different information about the molecule's structure.
You can have single bonds (one pair of shared electrons), double bonds (two pairs, like O₂), or triple bonds (three pairs, like N₂). The more pairs shared, the stronger the bond between those atoms.
Memory trick: Covalent = 'co-valent' = sharing valence (outer) electrons cooperatively!
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Giant Covalent Structures
Giant covalent structures are like massive 3D puzzles where millions of atoms are joined by covalent bonds. The three allotropes of carbon - diamond, graphite, and graphene - show how the same element can have completely different properties.
Diamond has four covalent bonds per carbon atom, creating an incredibly hard, rigid network. Graphite has three bonds per carbon, forming layers that can slide over each other, making it soft and slippery (perfect for pencils!).
Graphene is essentially one layer of graphite - it's incredibly strong yet thin and light. All three have high melting points because you need to break many covalent bonds to melt them.
Amazing fact: Graphite conducts electricity because it has delocalised electrons between layers, but diamond doesn't because all electrons are locked in bonds!
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We thought you’d never ask...
What is the Knowunity AI companion?
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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