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Nov 25, 2025
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Understanding the Atom and Its Subatomic Particles
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@thatweebudontknow
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The Basic Structure of Matter
Matter is everything that takes up space and has mass in our world. Whether it's the air you breathe or the phone in your hand, it's all made up of incredibly tiny particles called atoms. These atoms can exist independently or connect with others.
When a collection of the same kind of atoms exists together, we call it an element (like pure oxygen or gold). When different elements connect, they form a compound (like water or table salt).
Every atom contains three main subatomic particles: electrons, protons, and neutrons. Each has unique properties that define how atoms behave:
- Electrons are tiny, negatively charged (-1) particles with only 1/1840 the mass of other particles
- Protons carry a positive charge (+1) and have significant mass
- Neutrons have no charge but similar mass to protons
Fun Fact: If you enlarged an atom to the size of a football stadium, the nucleus (containing protons and neutrons) would only be the size of a pea in the center, with electrons moving throughout the rest of the space!
The Bohr model helps us visualize atoms with electrons orbiting around a central nucleus, similar to planets around the sun.
Identifying Elements and Their Variations
Protons give atoms their identity. The number of protons (called the atomic number) determines which element an atom is. For example, hydrogen always has 1 proton, carbon always has 6, and mercury always has 80. No two elements can have the same number of protons.
Electrons determine an atom's charge. To find the charge of an atom, simply subtract the number of electrons from the number of protons. When these numbers are equal, the atom is neutral. When they differ, the atom becomes an ion with a positive or negative charge.
Neutrons create different versions of the same element called isotopes. While isotopes have identical proton counts (same element), their different neutron counts give them different masses. The mass number helps identify isotopes by adding protons and neutrons together.
Elements are represented by one or two-letter symbols. When two letters are used, only the first is capitalized (like Ne for neon). These symbols can be written with additional information:
- Top left: mass number
- Bottom left: atomic number (protons)
- Top right: charge
- Bottom right: number of atoms connected together
Remember This: The periodic table shows atomic numbers and average atomic mass for each element, but doesn't directly tell you the mass number of specific isotopes or their charges.
Making Sense of Atomic Numbers
The key to understanding atoms lies in knowing what each number represents. Let's break it down into simple formulas:
Atomic number equals the number of protons. This never changes for a particular element and is the element's identity card. Every carbon atom in the universe has 6 protons—no exceptions!
To find an atom's charge, subtract the number of electrons from the number of protons. If there are more protons than electrons, the charge is positive. If there are more electrons than protons, the charge is negative.
The mass number equals protons plus neutrons. Since electrons have almost no mass, only protons and neutrons significantly contribute to an atom's mass. This number helps identify different isotopes of the same element.
When using the periodic table, remember it only shows the atomic number and average atomic mass of an element. The representation of elements inside the periodic table differs from how we write them in chemical formulas.
Study Tip: Create flashcards with an element symbol on one side and its properties on the other. Quiz yourself on identifying the number of protons, electrons, and neutrons for different elements and their isotopes!
We thought you’d never ask...
What is the Knowunity AI companion?
Our AI companion is specifically built for the needs of students. Based on the millions of content pieces we have on the platform we can provide truly meaningful and relevant answers to students. But its not only about answers, the companion is even more about guiding students through their daily learning challenges, with personalised study plans, quizzes or content pieces in the chat and 100% personalisation based on the students skills and developments.
Where can I download the Knowunity app?
You can download the app in the Google Play Store and in the Apple App Store.
Is Knowunity really free of charge?
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
Can't find what you're looking for? Explore other subjects.
Students love us — and so will you.
4.9/5
App Store
4.8/5
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
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
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
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
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 app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
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
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
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
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
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 app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
Paul T
iOS user
Understanding the Atom and Its Subatomic Particles
thatweebudontknow
@thatweebudontknow
Atoms are the tiny building blocks of all matter around us. Everything that takes up space and has mass is made of atoms, which combine to form elements and compounds. Let's explore the fascinating world of atomic structure and how... Show more
The Basic Structure of Matter
Matter is everything that takes up space and has mass in our world. Whether it's the air you breathe or the phone in your hand, it's all made up of incredibly tiny particles called atoms. These atoms can exist independently or connect with others.
When a collection of the same kind of atoms exists together, we call it an element (like pure oxygen or gold). When different elements connect, they form a compound (like water or table salt).
Every atom contains three main subatomic particles: electrons, protons, and neutrons. Each has unique properties that define how atoms behave:
- Electrons are tiny, negatively charged (-1) particles with only 1/1840 the mass of other particles
- Protons carry a positive charge (+1) and have significant mass
- Neutrons have no charge but similar mass to protons
Fun Fact: If you enlarged an atom to the size of a football stadium, the nucleus (containing protons and neutrons) would only be the size of a pea in the center, with electrons moving throughout the rest of the space!
The Bohr model helps us visualize atoms with electrons orbiting around a central nucleus, similar to planets around the sun.
Sign up to see the contentIt's free!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Identifying Elements and Their Variations
Protons give atoms their identity. The number of protons (called the atomic number) determines which element an atom is. For example, hydrogen always has 1 proton, carbon always has 6, and mercury always has 80. No two elements can have the same number of protons.
Electrons determine an atom's charge. To find the charge of an atom, simply subtract the number of electrons from the number of protons. When these numbers are equal, the atom is neutral. When they differ, the atom becomes an ion with a positive or negative charge.
Neutrons create different versions of the same element called isotopes. While isotopes have identical proton counts (same element), their different neutron counts give them different masses. The mass number helps identify isotopes by adding protons and neutrons together.
Elements are represented by one or two-letter symbols. When two letters are used, only the first is capitalized (like Ne for neon). These symbols can be written with additional information:
- Top left: mass number
- Bottom left: atomic number (protons)
- Top right: charge
- Bottom right: number of atoms connected together
Remember This: The periodic table shows atomic numbers and average atomic mass for each element, but doesn't directly tell you the mass number of specific isotopes or their charges.
Sign up to see the contentIt's free!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Making Sense of Atomic Numbers
The key to understanding atoms lies in knowing what each number represents. Let's break it down into simple formulas:
Atomic number equals the number of protons. This never changes for a particular element and is the element's identity card. Every carbon atom in the universe has 6 protons—no exceptions!
To find an atom's charge, subtract the number of electrons from the number of protons. If there are more protons than electrons, the charge is positive. If there are more electrons than protons, the charge is negative.
The mass number equals protons plus neutrons. Since electrons have almost no mass, only protons and neutrons significantly contribute to an atom's mass. This number helps identify different isotopes of the same element.
When using the periodic table, remember it only shows the atomic number and average atomic mass of an element. The representation of elements inside the periodic table differs from how we write them in chemical formulas.
Study Tip: Create flashcards with an element symbol on one side and its properties on the other. Quiz yourself on identifying the number of protons, electrons, and neutrons for different elements and their isotopes!
We thought you’d never ask...
What is the Knowunity AI companion?
Our AI companion is specifically built for the needs of students. Based on the millions of content pieces we have on the platform we can provide truly meaningful and relevant answers to students. But its not only about answers, the companion is even more about guiding students through their daily learning challenges, with personalised study plans, quizzes or content pieces in the chat and 100% personalisation based on the students skills and developments.
Where can I download the Knowunity app?
You can download the app in the Google Play Store and in the Apple App Store.
Is Knowunity really free of charge?
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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Can't find what you're looking for? Explore other subjects.
Students love us — and so will you.
4.9/5
App Store
4.8/5
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
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
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
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
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 app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
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
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
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
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
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 app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
Paul T
iOS user