Nuclear chemistry explores how atomic nuclei react, transform, and emit... Show more
AlgebraSign up to see the contentIt's free!
Access to all documents
Improve your grades
Join milions of students
60
•
Feb 3, 2026
•
Understanding Nuclear Chemistry
Katy Hodge
@theonlykatinthehat
1 / 3
Nuclear Chemistry Fundamentals
Nuclear reactions differ completely from the chemical reactions you're familiar with. In chemical reactions, atoms are conserved and electrons drive the process. But in nuclear reactions, atoms can actually be created or destroyed, and mass isn't always conserved!
When nuclei become unstable, they undergo transmutation—the process of converting into a different nucleus entirely. What makes a nucleus unstable? The main culprit is too many protons packed together. Since protons all have positive charges, they naturally repel each other. Neutrons act as "spacers" between protons to help stabilize the nucleus.
Scientists use something called the "Band of Stability" to determine if a nucleus is stable. This band represents the ideal neutron-to-proton ratios. For lighter elements, a 1:1 ratio works well, but as elements get heavier, they need more neutrons per proton (up to 1.5:1) to remain stable.
Did you know? The nucleus of an atom is incredibly tiny, yet it contains nearly all of the atom's mass. Despite its size, the instability of certain nuclei can release enormous amounts of energy!
Radioactive Decay
When nuclei fall outside the Band of Stability, they undergo radioactive decay to reach stability. Think of it as nature's way of fixing unstable atoms! These decay processes change the neutron-to-proton ratio by adjusting the number of protons, neutrons, or both.
There are three main types of radioactive decay you need to know. Alpha decay occurs when a nucleus emits an alpha particle—essentially a helium nucleus with 2 protons and 2 neutrons. Alpha particles have a positive charge and can be stopped by something as thin as paper!
Beta decay happens when an unstable neutron converts into a proton and emits an electron (the beta particle). These negatively charged particles can penetrate paper but are stopped by aluminum. Meanwhile, gamma decay produces high-energy photons that have no mass or charge and often accompanies other decay types.
Each decay type has different penetrating abilities. Alpha particles are stopped by paper, beta particles by aluminum, and gamma rays sometimes require lead shielding to be blocked completely.
Important! When studying radioactive decay, remember that each decay type changes the atom in specific ways: alpha decay decreases both mass number and atomic number, while beta decay increases the atomic number but keeps the mass number the same.
Nuclear Equations
Writing nuclear equations for radioactive decay might seem tricky at first, but there's one key rule: the total number of protons and neutrons must be conserved on both sides of the equation.
For example, when a radioactive element like Radon-222 (²²²Rn₈₆) undergoes alpha decay, it emits a helium nucleus (⁴He₂). To write this equation, you need to account for all particles and their properties.
After alpha decay, the mass number of the original atom decreases by 4 (the mass of the alpha particle), and the atomic number decreases by 2 (the number of protons in the alpha particle). So Radon-222 would transform into Polonium-218 (²¹⁸Po₈₄).
The equation would look like this: ²²²Rn₈₆ → ²¹⁸Po₈₄ + ⁴He₂
Pro tip: When balancing nuclear equations, first identify the type of decay, then adjust the product's atomic number and mass number accordingly. For alpha decay, subtract 4 from the mass number and 2 from the atomic number.
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.
Most popular content in Chemistry
Most popular content
Can't find what you're looking for? Explore other subjects.
Students love us — and so will you.
4.6/5
App Store
4.7/5
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 Knowunity AI. 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 Knowunity AI. 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 Nuclear Chemistry
Katy Hodge
@theonlykatinthehat
Nuclear chemistry explores how atomic nuclei react, transform, and emit energy. Unlike chemical reactions that rearrange electrons, nuclear reactions involve changes to the nucleus itself, often resulting in the transformation of one element into another through radioactive decay.
Nuclear Chemistry Fundamentals
Nuclear reactions differ completely from the chemical reactions you're familiar with. In chemical reactions, atoms are conserved and electrons drive the process. But in nuclear reactions, atoms can actually be created or destroyed, and mass isn't always conserved!
When nuclei become unstable, they undergo transmutation—the process of converting into a different nucleus entirely. What makes a nucleus unstable? The main culprit is too many protons packed together. Since protons all have positive charges, they naturally repel each other. Neutrons act as "spacers" between protons to help stabilize the nucleus.
Scientists use something called the "Band of Stability" to determine if a nucleus is stable. This band represents the ideal neutron-to-proton ratios. For lighter elements, a 1:1 ratio works well, but as elements get heavier, they need more neutrons per proton (up to 1.5:1) to remain stable.
Did you know? The nucleus of an atom is incredibly tiny, yet it contains nearly all of the atom's mass. Despite its size, the instability of certain nuclei can release enormous amounts of energy!
Sign up to see the contentIt's free!
Access to all documents
Improve your grades
Join milions of students
Radioactive Decay
When nuclei fall outside the Band of Stability, they undergo radioactive decay to reach stability. Think of it as nature's way of fixing unstable atoms! These decay processes change the neutron-to-proton ratio by adjusting the number of protons, neutrons, or both.
There are three main types of radioactive decay you need to know. Alpha decay occurs when a nucleus emits an alpha particle—essentially a helium nucleus with 2 protons and 2 neutrons. Alpha particles have a positive charge and can be stopped by something as thin as paper!
Beta decay happens when an unstable neutron converts into a proton and emits an electron (the beta particle). These negatively charged particles can penetrate paper but are stopped by aluminum. Meanwhile, gamma decay produces high-energy photons that have no mass or charge and often accompanies other decay types.
Each decay type has different penetrating abilities. Alpha particles are stopped by paper, beta particles by aluminum, and gamma rays sometimes require lead shielding to be blocked completely.
Important! When studying radioactive decay, remember that each decay type changes the atom in specific ways: alpha decay decreases both mass number and atomic number, while beta decay increases the atomic number but keeps the mass number the same.
Sign up to see the contentIt's free!
Access to all documents
Improve your grades
Join milions of students
Nuclear Equations
Writing nuclear equations for radioactive decay might seem tricky at first, but there's one key rule: the total number of protons and neutrons must be conserved on both sides of the equation.
For example, when a radioactive element like Radon-222 (²²²Rn₈₆) undergoes alpha decay, it emits a helium nucleus (⁴He₂). To write this equation, you need to account for all particles and their properties.
After alpha decay, the mass number of the original atom decreases by 4 (the mass of the alpha particle), and the atomic number decreases by 2 (the number of protons in the alpha particle). So Radon-222 would transform into Polonium-218 (²¹⁸Po₈₄).
The equation would look like this: ²²²Rn₈₆ → ²¹⁸Po₈₄ + ⁴He₂
Pro tip: When balancing nuclear equations, first identify the type of decay, then adjust the product's atomic number and mass number accordingly. For alpha decay, subtract 4 from the mass number and 2 from the atomic number.
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.
0
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Practice Test ✓ Essay Outlines
Practice Test
Quiz
Flashcards
Essay
Similar Content
Ionization Energy Explained
Explore the factors influencing ionization energy, including trends across periods and down groups in the periodic table. This summary covers atomic structure, electron configurations, isotopes, and mass spectrometry, providing a comprehensive understanding of how atomic properties affect ionization. Ideal for students studying chemistry concepts related to atomic structure and periodic trends.
Chemistry12
Electronic Structure of Atoms outline
outline and notes of Chapter 6: Electronic Structure of Atoms from Chemistry the Central science
Chemistry10th
Modern Atomic Theory
Notes about the modern atomic theory and what it means
ChemistryChemistry Scientists and their Contributions
This lists the different chemistry scientists and their contributions.
Chemistry10th
Atoms
It’s talks about the creators of each atom and what they ere made for.
AP ChemistryThe Quantum Model
The basics of the quantum model and the four quantum numbers.
Chemistry10th
Most popular content in Chemistry
Most popular content
Can't find what you're looking for? Explore other subjects.
Students love us — and so will you.
4.6/5
App Store
4.7/5
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 Knowunity AI. 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 Knowunity AI. 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