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19
3
Emi
10/04/2023
Chemistry
Atomic theory
550
•
10 Apr 2023
•
Atomic theory and structure are fundamental concepts in chemistry, explaining... Show more
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Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
This page delves deeper into the arrangement of electrons and introduces the concepts of atomic number and mass number, which are essential for understanding atomic number and mass number in elements gcse.
Definition: Atoms are electrically neutral, meaning the number of electrons equals the number of protons.
The atomic number, also known as the proton number, is introduced as a fundamental property of elements.
Definition: The atomic number is the number of protons in an atom and is unique for each element.
An example is provided using aluminum, which has an atomic number of 13, meaning it has 13 protons and 13 electrons. Its electronic configuration is given as 2,8,3.
Highlight: On the periodic table, atomic numbers increase in order.
The concept of mass number is then explained:
Definition: The mass number is the total number of protons and neutrons in an atom's nucleus.
The page demonstrates how to calculate the number of neutrons by subtracting the atomic number from the mass number.
Example: For Cobalt (Co), with a mass number of 59 and an atomic number of 27, the number of neutrons is 59 - 27 = 32.
The page concludes with exercises on finding atomic numbers, mass numbers, and calculating the number of neutrons for various elements using the periodic table. This information is crucial for students studying detailed explanation of electron configuration in atoms class 9 and higher levels.
This page focuses on the arrangement of electrons in atoms, which is essential for understanding chemical bonding and reactivity. This knowledge forms the basis for detailed explanation of electron configuration in atoms pdf.
Definition: Electrons are arranged around the nucleus in energy levels or shells, with the lowest energy level closest to the nucleus.
The page explains that electrons are attracted to the positively charged nucleus and fill the lower energy levels first. It provides a visual representation of the first three energy levels, showing their electron capacities:
Example: Lithium, with 3 electrons, has 2 in the first shell and 1 in the outer shell.
The concept of electronic configuration is introduced, using a notation system that represents the number of electrons in each shell.
Example: Chlorine, with an atomic number of 17, has an electronic configuration of 2,8,7.
Highlight: The number of electrons in the outermost shell determines the element's group in the periodic table.
The page concludes with a note on drawing electron shell diagrams, advising students to arrange electrons in pairs and evenly around the circle to avoid losing count.
This information is crucial for understanding the electronic configuration of first 20 elements and beyond, providing a foundation for more advanced topics in chemistry such as chemical bonding and periodic trends.
This page introduces the fundamental concepts of atomic theory and structure, providing a foundation for understanding the composition of matter at the atomic level.
Definition: An atom is the smallest part of an element that retains its chemical properties.
The page explains that all substances are made up of atoms, and there are millions of substances naturally composed of elements. Compounds are formed when two or more elements chemically combine.
Highlight: New atoms are created in stars or through nuclear processes.
The structure of an atom is described, consisting of a small central nucleus made up of protons and neutrons, surrounded by tiny electrons. These components are referred to as subatomic particles.
Vocabulary: Subatomic particles are the fundamental components of an atom: protons, neutrons, and electrons.
A table is provided detailing the properties of these subatomic particles:
Highlight: Virtually all of an atom's mass is concentrated in the nucleus, as electrons have negligible mass.
This information is crucial for understanding atomic number and mass number in elements class 9 and beyond, laying the groundwork for more advanced concepts in atomic structure.
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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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
Atomic theory and structure are fundamental concepts in chemistry, explaining the composition of matter at its most basic level. This summary covers key aspects including the structure of atoms, subatomic particles, atomic number, mass number, and electron configuration. Full notes... Show more
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Improve your grades
Join milions of students
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This page delves deeper into the arrangement of electrons and introduces the concepts of atomic number and mass number, which are essential for understanding atomic number and mass number in elements gcse.
Definition: Atoms are electrically neutral, meaning the number of electrons equals the number of protons.
The atomic number, also known as the proton number, is introduced as a fundamental property of elements.
Definition: The atomic number is the number of protons in an atom and is unique for each element.
An example is provided using aluminum, which has an atomic number of 13, meaning it has 13 protons and 13 electrons. Its electronic configuration is given as 2,8,3.
Highlight: On the periodic table, atomic numbers increase in order.
The concept of mass number is then explained:
Definition: The mass number is the total number of protons and neutrons in an atom's nucleus.
The page demonstrates how to calculate the number of neutrons by subtracting the atomic number from the mass number.
Example: For Cobalt (Co), with a mass number of 59 and an atomic number of 27, the number of neutrons is 59 - 27 = 32.
The page concludes with exercises on finding atomic numbers, mass numbers, and calculating the number of neutrons for various elements using the periodic table. This information is crucial for students studying detailed explanation of electron configuration in atoms class 9 and higher levels.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
This page focuses on the arrangement of electrons in atoms, which is essential for understanding chemical bonding and reactivity. This knowledge forms the basis for detailed explanation of electron configuration in atoms pdf.
Definition: Electrons are arranged around the nucleus in energy levels or shells, with the lowest energy level closest to the nucleus.
The page explains that electrons are attracted to the positively charged nucleus and fill the lower energy levels first. It provides a visual representation of the first three energy levels, showing their electron capacities:
Example: Lithium, with 3 electrons, has 2 in the first shell and 1 in the outer shell.
The concept of electronic configuration is introduced, using a notation system that represents the number of electrons in each shell.
Example: Chlorine, with an atomic number of 17, has an electronic configuration of 2,8,7.
Highlight: The number of electrons in the outermost shell determines the element's group in the periodic table.
The page concludes with a note on drawing electron shell diagrams, advising students to arrange electrons in pairs and evenly around the circle to avoid losing count.
This information is crucial for understanding the electronic configuration of first 20 elements and beyond, providing a foundation for more advanced topics in chemistry such as chemical bonding and periodic trends.
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 the fundamental concepts of atomic theory and structure, providing a foundation for understanding the composition of matter at the atomic level.
Definition: An atom is the smallest part of an element that retains its chemical properties.
The page explains that all substances are made up of atoms, and there are millions of substances naturally composed of elements. Compounds are formed when two or more elements chemically combine.
Highlight: New atoms are created in stars or through nuclear processes.
The structure of an atom is described, consisting of a small central nucleus made up of protons and neutrons, surrounded by tiny electrons. These components are referred to as subatomic particles.
Vocabulary: Subatomic particles are the fundamental components of an atom: protons, neutrons, and electrons.
A table is provided detailing the properties of these subatomic particles:
Highlight: Virtually all of an atom's mass is concentrated in the nucleus, as electrons have negligible mass.
This information is crucial for understanding atomic number and mass number in elements class 9 and beyond, laying the groundwork for more advanced concepts in atomic structure.
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.
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
App 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
