Maths
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Responding to change (a2 only)
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Organisms respond to changes in their internal and external environments (a-level only)
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1l the quest for political stability: germany, 1871-1991
Britain & the wider world: 1745 -1901
The cold war
Inter-war germany
Medieval period: 1066 -1509
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
World war two & the holocaust
2n revolution and dictatorship: russia, 1917-1953
2s the making of modern britain, 1951-2007
World war one
Britain: 1509 -1745
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Chemistry
1 Dec 2025
151
2 pages
Ellie ๐๐ฆโจ @ellie_vgzv
This atomic structure and isotopes study guidecovers key concepts in atomic structure, elements, compounds, and chemical reactions.... Show more
This page delves deeper into atomic structure and chemical reactions, focusing on the conservation of mass and the formation of ions. It explains how the mass number of an atom is calculated and introduces the concept of ions, which are atoms or groups of atoms with an electric charge.
Definition The mass number of an atom is the sum of its protons and neutrons.
Vocabulary An ion is an atom or group of atoms that has gained or lost electrons, resulting in a positive or negative charge.
The page describes how elements can gain or lose electrons during chemical reactions, leading to the formation of positive or negative ions. It also outlines the general behavior of metals and non-metals in these processes.
Example Metals tend to lose electrons, forming positive ions, while non-metals gain electrons to form negative ions.
Historical contributions to atomic theory are mentioned, including J.J. Thomson's discovery of electrons and Rutherford's gold foil experiment, which led to the nuclear model of the atom.
Highlight Rutherford's experiment showed that most of an atom's mass is concentrated in a small, positively charged nucleus.
The concept of isotopes is introduced, explaining that these are atoms of the same element with different numbers of neutrons.
Definition Isotopes are atoms with the same number of protons but different numbers of neutrons in their nuclei.
This page provides a comprehensive overview of atomic structure, ion formation, and the historical experiments that shaped our understanding of the atom, reinforcing the atomic structure and isotopes study guide with practical examples and key discoveries in the field.
This page introduces fundamental concepts of atomic structure and chemistry. It begins by defining key terms essential for understanding the building blocks of matter. The atomic model is presented, showing the arrangement of protons, neutrons, and electrons within an atom. The page also distinguishes between elements, compounds, and mixtures, providing visual representations for each.
Vocabulary An atom is defined as a single particle that makes up everything in the universe.
Definition The atomic number is the number of protons in an atom, which determines the element's identity.
Example Oxygen is represented as an element with its specific atomic structure, while water (H2O) is shown as a compound of hydrogen and oxygen.
Highlight The atomic mass of an element can be calculated by adding the number of protons and neutrons, while the number of electrons is equal to the number of protons in a neutral atom.
The page concludes with diagrams illustrating the differences between elements, compounds, and mixtures at the atomic and molecular level, providing a visual aid for understanding these fundamental chemical concepts.
Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.
You can download the app from Google Play Store and Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help โ all at your fingertips.
10
Smart Tools NEW
Transform this note into: โ 50+ Practice Questions โ Interactive Flashcards โ Full Mock Exam โ Essay Outlines
Explore the fundamentals of atomic structure, including subatomic particles, electron configurations, and the organization of the periodic table. This summary covers key concepts such as atomic bonding, states of matter, and the distinction between elements, compounds, and mixtures. Ideal for students studying Chemistry and Biology.
BiologyExplore the fundamental concepts of elements, isotopes, and relative atomic mass in this detailed summary. Learn how isotopes differ, the significance of atomic mass units (amu), and how to calculate the relative atomic mass using real examples like chlorine. Ideal for chemistry students seeking clarity on these essential topics.
ChemistryExplore the fundamental concepts of atoms, ions, isotopes, and their properties. This summary covers atomic structure, the formation of ions, the distinction between elements, compounds, and mixtures, and the historical development of atomic theory. Ideal for GCSE Chemistry students.
ChemistryExplore the fundamentals of atomic structure, including subatomic particles, atomic mass, and the distinction between elements, compounds, and mixtures. This summary covers key concepts such as protons, neutrons, electrons, and how they form molecules and compounds. Ideal for students studying chemistry.
ChemistryExplore the fundamental concepts of atomic structure and ion formation in this GCSE chemistry summary. Learn about protons, neutrons, electrons, and how atoms become ions through the loss or gain of electrons. Ideal for students seeking clarity on cations and the balance of charges within atoms.
ChemistryExplore the fundamentals of atomic structure and bonding, including atomic numbers, mass numbers, ionic and covalent bonds, and the periodic table. This summary covers key concepts essential for understanding chemical properties and compound formation. Ideal for chemistry students preparing for exams.
ChemistryApp Store
Google Play
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because itโs too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didnโt even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as Iโm sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH ๐๐๐ฒ๐ค๐โจ๐๐ฎ
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because itโs too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didnโt even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as Iโm sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH ๐๐๐ฒ๐ค๐โจ๐๐ฎ
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
Ellie ๐๐ฆโจ
@ellie_vgzv
This atomic structure and isotopes study guidecovers key concepts in atomic structure, elements, compounds, and chemical reactions. It explores the fundamental particles of atoms, their arrangement, and how they interact in various chemical processes. The guide also delves into... Show more
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
This page delves deeper into atomic structure and chemical reactions, focusing on the conservation of mass and the formation of ions. It explains how the mass number of an atom is calculated and introduces the concept of ions, which are atoms or groups of atoms with an electric charge.
Definition: The mass number of an atom is the sum of its protons and neutrons.
Vocabulary: An ion is an atom or group of atoms that has gained or lost electrons, resulting in a positive or negative charge.
The page describes how elements can gain or lose electrons during chemical reactions, leading to the formation of positive or negative ions. It also outlines the general behavior of metals and non-metals in these processes.
Example: Metals tend to lose electrons, forming positive ions, while non-metals gain electrons to form negative ions.
Historical contributions to atomic theory are mentioned, including J.J. Thomson's discovery of electrons and Rutherford's gold foil experiment, which led to the nuclear model of the atom.
Highlight: Rutherford's experiment showed that most of an atom's mass is concentrated in a small, positively charged nucleus.
The concept of isotopes is introduced, explaining that these are atoms of the same element with different numbers of neutrons.
Definition: Isotopes are atoms with the same number of protons but different numbers of neutrons in their nuclei.
This page provides a comprehensive overview of atomic structure, ion formation, and the historical experiments that shaped our understanding of the atom, reinforcing the atomic structure and isotopes study guide with practical examples and key discoveries in the field.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
This page introduces fundamental concepts of atomic structure and chemistry. It begins by defining key terms essential for understanding the building blocks of matter. The atomic model is presented, showing the arrangement of protons, neutrons, and electrons within an atom. The page also distinguishes between elements, compounds, and mixtures, providing visual representations for each.
Vocabulary: An atom is defined as a single particle that makes up everything in the universe.
Definition: The atomic number is the number of protons in an atom, which determines the element's identity.
Example: Oxygen is represented as an element with its specific atomic structure, while water (H2O) is shown as a compound of hydrogen and oxygen.
Highlight: The atomic mass of an element can be calculated by adding the number of protons and neutrons, while the number of electrons is equal to the number of protons in a neutral atom.
The page concludes with diagrams illustrating the differences between elements, compounds, and mixtures at the atomic and molecular level, providing a visual aid for understanding these fundamental chemical concepts.
Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.
You can download the app from Google Play Store and Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help โ all at your fingertips.
10
Smart Tools NEW
Transform this note into: โ 50+ Practice Questions โ Interactive Flashcards โ Full Mock Exam โ Essay Outlines
Explore the fundamentals of atomic structure, including subatomic particles, electron configurations, and the organization of the periodic table. This summary covers key concepts such as atomic bonding, states of matter, and the distinction between elements, compounds, and mixtures. Ideal for students studying Chemistry and Biology.
BiologyExplore the fundamental concepts of elements, isotopes, and relative atomic mass in this detailed summary. Learn how isotopes differ, the significance of atomic mass units (amu), and how to calculate the relative atomic mass using real examples like chlorine. Ideal for chemistry students seeking clarity on these essential topics.
ChemistryExplore the fundamental concepts of atoms, ions, isotopes, and their properties. This summary covers atomic structure, the formation of ions, the distinction between elements, compounds, and mixtures, and the historical development of atomic theory. Ideal for GCSE Chemistry students.
ChemistryExplore the fundamentals of atomic structure, including subatomic particles, atomic mass, and the distinction between elements, compounds, and mixtures. This summary covers key concepts such as protons, neutrons, electrons, and how they form molecules and compounds. Ideal for students studying chemistry.
ChemistryExplore the fundamental concepts of atomic structure and ion formation in this GCSE chemistry summary. Learn about protons, neutrons, electrons, and how atoms become ions through the loss or gain of electrons. Ideal for students seeking clarity on cations and the balance of charges within atoms.
ChemistryExplore the fundamentals of atomic structure and bonding, including atomic numbers, mass numbers, ionic and covalent bonds, and the periodic table. This summary covers key concepts essential for understanding chemical properties and compound formation. Ideal for chemistry students preparing for exams.
ChemistryApp Store
Google Play
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because itโs too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didnโt even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as Iโm sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH ๐๐๐ฒ๐ค๐โจ๐๐ฎ
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because itโs too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didnโt even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as Iโm sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH ๐๐๐ฒ๐ค๐โจ๐๐ฎ
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
