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Britain & the wider world: 1745 -1901
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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
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Chemistry
12 Dec 2025
255
3 pages
Jordan @axurerain
Chemical bonding is everywhere around you - from the salt on your chips to the water you drink.... Show more
Ionic bonding happens when electrons jump from one atom to another, creating charged particles that attract each other like magnets. These ionic bonds create massive structures called giant ionic lattices - think of them as 3D networks of alternating positive and negative ions.
Here's what makes ionic compounds special they have sky-high melting and boiling points because breaking those electrostatic forces requires serious energy. Most dissolve brilliantly in water because the water molecules can pull the ions apart more easily than the ions can hold onto each other.
Covalent bonding works differently - atoms actually share electrons rather than stealing them. The covalent bond forms when electron clouds overlap, creating a strong attraction between the shared electrons and both atomic nuclei. Sometimes one atom provides both electrons in the shared pair, which we call a dative covalent bond.
Quick Tip Think ionic = transfer, covalent = share!
When drawing ionic equations, remember the golden rules split anything aqueous (aq) into ions, keep solids/liquids/gases whole, and cancel out identical ions from both sides.
Molecular geometry isn't random - it follows predictable patterns based on electron pairs. Bonding pairs spread out evenly to minimise repulsion, giving you shapes like linear (180°), trigonal planar (120°), and tetrahedral (109.5°). But lone pairs are bullies - they're more electron-dense and push bonding pairs closer together.
Electronegativity measures how desperately an atom wants to hog electrons in a bond. The Pauling Scale shows this increases as you go up groups and across periods (fluorine is the ultimate electron grabber). Three key factors control this atomic radius, nuclear charge, and electron shielding.
The electronegativity difference between atoms determines bond type massive differences (>1.8) create ionic bonds, moderate differences (0.5-1.8) give polar covalent bonds with partial charges, and tiny differences (0.1-0.5) produce non-polar covalent bonds.
Remember Polar dissolves polar - it's chemistry's version of "like attracts like"!
Just because a molecule contains polar bonds doesn't automatically make it polar overall - the shape matters too!
Intermolecular forces are the weak attractions between separate molecules - much weaker than the bonds within molecules but absolutely crucial for determining physical properties. There are three main types you need to master.
London forces exist between all molecules, even non-polar ones. Electrons constantly move around, creating temporary dipoles that induce dipoles in neighbouring molecules. These forces get stronger with more electrons - that's why noble gases have higher boiling points as you go down the group.
Permanent dipole-dipole forces occur between polar molecules where one end is slightly positive and the other slightly negative. These molecules line up with opposite charges attracting each other.
Hydrogen bonding is the strongest intermolecular force. It happens when hydrogen attached to nitrogen, oxygen, or fluorine gets attracted to lone pairs on these highly electronegative atoms in other molecules.
Key Insight More electrons = stronger London forces = higher boiling points!
Understanding these forces explains why water has such unusual properties and why some substances mix whilst others don't.
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.
1
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore the fundamental concepts of atomic structure, ionic and covalent bonding, and the properties of materials. This summary covers nanoparticles, giant covalent structures, metallic bonding, and the behavior of different compounds, providing essential insights for chemistry students. Ideal for exam preparation and revision.
ChemistryExplore the principles of electrolysis, including redox reactions, half-reactions, and the roles of anodes and cathodes. This summary covers key concepts such as electrolytic cells, Faraday's laws, and the significance of electrolytes in conducting electricity. Ideal for students preparing for exams or seeking a clear understanding of electrolysis processes.
Chemistrygrade 7+ gcse combined science notes
ChemistryBonding
ChemistryComprehensive resource for Year 12 students pursuing a Level 3 Diploma in Applied Science. This booklet covers essential topics including cell structure, chemical properties, and wave theory, providing clear explanations and key concepts to aid in your studies and exam preparation.
ChemistryExplore key concepts in oxidation and reduction, chemical bonding, and periodic trends. This summary covers reducing and oxidizing agents, intermolecular forces, and stoichiometry, providing essential insights for understanding chemical reactions and molecular structures.
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
Jordan
@axurerain
Chemical bonding is everywhere around you - from the salt on your chips to the water you drink. Understanding how atoms stick together and the forces between molecules will help you make sense of why materials behave the way they... Show more
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Ionic bonding happens when electrons jump from one atom to another, creating charged particles that attract each other like magnets. These ionic bonds create massive structures called giant ionic lattices - think of them as 3D networks of alternating positive and negative ions.
Here's what makes ionic compounds special: they have sky-high melting and boiling points because breaking those electrostatic forces requires serious energy. Most dissolve brilliantly in water because the water molecules can pull the ions apart more easily than the ions can hold onto each other.
Covalent bonding works differently - atoms actually share electrons rather than stealing them. The covalent bond forms when electron clouds overlap, creating a strong attraction between the shared electrons and both atomic nuclei. Sometimes one atom provides both electrons in the shared pair, which we call a dative covalent bond.
Quick Tip: Think ionic = transfer, covalent = share!
When drawing ionic equations, remember the golden rules: split anything aqueous (aq) into ions, keep solids/liquids/gases whole, and cancel out identical ions from both sides.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Molecular geometry isn't random - it follows predictable patterns based on electron pairs. Bonding pairs spread out evenly to minimise repulsion, giving you shapes like linear (180°), trigonal planar (120°), and tetrahedral (109.5°). But lone pairs are bullies - they're more electron-dense and push bonding pairs closer together.
Electronegativity measures how desperately an atom wants to hog electrons in a bond. The Pauling Scale shows this increases as you go up groups and across periods (fluorine is the ultimate electron grabber). Three key factors control this: atomic radius, nuclear charge, and electron shielding.
The electronegativity difference between atoms determines bond type: massive differences (>1.8) create ionic bonds, moderate differences (0.5-1.8) give polar covalent bonds with partial charges, and tiny differences (0.1-0.5) produce non-polar covalent bonds.
Remember: Polar dissolves polar - it's chemistry's version of "like attracts like"!
Just because a molecule contains polar bonds doesn't automatically make it polar overall - the shape matters too!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Intermolecular forces are the weak attractions between separate molecules - much weaker than the bonds within molecules but absolutely crucial for determining physical properties. There are three main types you need to master.
London forces exist between all molecules, even non-polar ones. Electrons constantly move around, creating temporary dipoles that induce dipoles in neighbouring molecules. These forces get stronger with more electrons - that's why noble gases have higher boiling points as you go down the group.
Permanent dipole-dipole forces occur between polar molecules where one end is slightly positive and the other slightly negative. These molecules line up with opposite charges attracting each other.
Hydrogen bonding is the strongest intermolecular force. It happens when hydrogen attached to nitrogen, oxygen, or fluorine gets attracted to lone pairs on these highly electronegative atoms in other molecules.
Key Insight: More electrons = stronger London forces = higher boiling points!
Understanding these forces explains why water has such unusual properties and why some substances mix whilst others don't.
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.
1
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore the fundamental concepts of atomic structure, ionic and covalent bonding, and the properties of materials. This summary covers nanoparticles, giant covalent structures, metallic bonding, and the behavior of different compounds, providing essential insights for chemistry students. Ideal for exam preparation and revision.
ChemistryExplore the principles of electrolysis, including redox reactions, half-reactions, and the roles of anodes and cathodes. This summary covers key concepts such as electrolytic cells, Faraday's laws, and the significance of electrolytes in conducting electricity. Ideal for students preparing for exams or seeking a clear understanding of electrolysis processes.
Chemistrygrade 7+ gcse combined science notes
ChemistryBonding
ChemistryComprehensive resource for Year 12 students pursuing a Level 3 Diploma in Applied Science. This booklet covers essential topics including cell structure, chemical properties, and wave theory, providing clear explanations and key concepts to aid in your studies and exam preparation.
ChemistryExplore key concepts in oxidation and reduction, chemical bonding, and periodic trends. This summary covers reducing and oxidizing agents, intermolecular forces, and stoichiometry, providing essential insights for understanding chemical reactions and molecular structures.
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