Chemistry introduces us to the fascinating world of matter and... Show more
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Dec 9, 2025
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Understanding the Fundamentals of Matter
M
Myah Nelson
@yahelson_lmgg
1 / 3
Chemical Compounds & Changes to Matter
Chemical compounds aren't permanent like elements - they can be broken down or transformed. What makes compounds interesting is that they have completely different properties than the elements they're made from. Take sodium (a deadly metal) and chlorine (a deadly gas) - together they form table salt (NaCl), which is essential for life!
When matter changes, it happens in two main ways. Physical changes don't alter chemical composition - like crumpling aluminum foil, melting ice, or mixing substances together. Chemical changes, however, transform substances into something new through chemical reactions where bonds are broken and formed.
Compounds consist of atoms from two or more elements bonded together in fixed ratios. The smallest particle of a compound is a molecule. Elements can exist in different forms: monoatomic (single atoms like Fe or Ca), diatomic (two bonded atoms like O₂ or N₂), or polyatomic (three or more bonded atoms like P₄ or S₈).
💡 Remember this simple trick: If a substance has changed into something completely different with new properties, it's undergone a chemical change. If it looks different but is still fundamentally the same substance, it's just a physical change.
Classification of Matter & Element Properties
Pure substances have constant composition where every particle is the same. They include elements (the simplest stable units that cannot be broken down further) and compounds (formed when elements combine). Unlike compounds, elements are permanent and cannot be decomposed into simpler substances.
Mixtures contain two or more pure substances combined together with variable composition. They come in two types: homogeneous mixtures (solutions with even composition throughout) and heterogeneous mixtures (uneven composition with visible layers or regions).
Elements are identified by their names and chemical symbols (one capitalized letter or two letters with the first capitalized). The periodic table organizes all 118 elements, though only 81 occur naturally. Each element has distinctive properties that help us identify and use them.
Matter can be described through its properties: Physical properties are characteristics you can observe without changing the substance's identity - color, texture, melting point, density, and solubility. Chemical properties describe how substances react (or don't react) with other substances like oxygen, water, acids, or bases.
🔍 When studying elements, focus on patterns of behavior rather than memorizing individual properties. The periodic table is organized specifically to help you predict how elements will behave based on their position!
Element Classifications
Metals dominate the left side of the periodic table and share common traits: they're typically solid at room temperature (except mercury), have high melting and boiling points, and appear shiny. You can bend and shape metals (they're malleable) and stretch them into wires (they're ductile). Metals only react with non-metals and conduct heat and electricity well.
Non-metals have almost opposite properties from metals. They typically have lower melting and boiling points, look dull rather than shiny, and tend to be soft or brittle. Unlike metals, non-metals are highly reactive with practically everything - other non-metals, metals, and even themselves! They're poor conductors, making them useful as insulators.
Between these groups are the semimetals (or metalloids), which exhibit properties of both metals and non-metals. They function as semiconductors, making them critically important for modern electronics and technology.
🔑 The distinct properties of metals, non-metals, and semimetals explain why certain materials are chosen for specific applications - from copper wires for electricity to silicon chips for computers!
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Most popular content: Properties of Matter
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4.9/5
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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 Fundamentals of Matter
M
Myah Nelson
@yahelson_lmgg
Chemistry introduces us to the fascinating world of matter and how it behaves. Understanding chemical compounds and their properties is fundamental to making sense of everything around us. This summary breaks down the key concepts about chemical compounds, matter classification,... Show more
Chemical Compounds & Changes to Matter
Chemical compounds aren't permanent like elements - they can be broken down or transformed. What makes compounds interesting is that they have completely different properties than the elements they're made from. Take sodium (a deadly metal) and chlorine (a deadly gas) - together they form table salt (NaCl), which is essential for life!
When matter changes, it happens in two main ways. Physical changes don't alter chemical composition - like crumpling aluminum foil, melting ice, or mixing substances together. Chemical changes, however, transform substances into something new through chemical reactions where bonds are broken and formed.
Compounds consist of atoms from two or more elements bonded together in fixed ratios. The smallest particle of a compound is a molecule. Elements can exist in different forms: monoatomic (single atoms like Fe or Ca), diatomic (two bonded atoms like O₂ or N₂), or polyatomic (three or more bonded atoms like P₄ or S₈).
💡 Remember this simple trick: If a substance has changed into something completely different with new properties, it's undergone a chemical change. If it looks different but is still fundamentally the same substance, it's just a physical change.
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Classification of Matter & Element Properties
Pure substances have constant composition where every particle is the same. They include elements (the simplest stable units that cannot be broken down further) and compounds (formed when elements combine). Unlike compounds, elements are permanent and cannot be decomposed into simpler substances.
Mixtures contain two or more pure substances combined together with variable composition. They come in two types: homogeneous mixtures (solutions with even composition throughout) and heterogeneous mixtures (uneven composition with visible layers or regions).
Elements are identified by their names and chemical symbols (one capitalized letter or two letters with the first capitalized). The periodic table organizes all 118 elements, though only 81 occur naturally. Each element has distinctive properties that help us identify and use them.
Matter can be described through its properties: Physical properties are characteristics you can observe without changing the substance's identity - color, texture, melting point, density, and solubility. Chemical properties describe how substances react (or don't react) with other substances like oxygen, water, acids, or bases.
🔍 When studying elements, focus on patterns of behavior rather than memorizing individual properties. The periodic table is organized specifically to help you predict how elements will behave based on their position!
Sign up to see the contentIt's free!
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Improve your grades
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Element Classifications
Metals dominate the left side of the periodic table and share common traits: they're typically solid at room temperature (except mercury), have high melting and boiling points, and appear shiny. You can bend and shape metals (they're malleable) and stretch them into wires (they're ductile). Metals only react with non-metals and conduct heat and electricity well.
Non-metals have almost opposite properties from metals. They typically have lower melting and boiling points, look dull rather than shiny, and tend to be soft or brittle. Unlike metals, non-metals are highly reactive with practically everything - other non-metals, metals, and even themselves! They're poor conductors, making them useful as insulators.
Between these groups are the semimetals (or metalloids), which exhibit properties of both metals and non-metals. They function as semiconductors, making them critically important for modern electronics and technology.
🔑 The distinct properties of metals, non-metals, and semimetals explain why certain materials are chosen for specific applications - from copper wires for electricity to silicon chips for computers!
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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4.9/5
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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