Subjects
Biology
Chemistry
AP Chemistry
English
AP English Literature
Earth and Space Science
Nov 25, 2025
174
3 pages
Rocks, minerals, and soil form the foundation of Earth's crust and are essential to understanding our planet. These... Show more
Rocks are solid materials formed through three main processes heat, pressure, or layering. They fall into three major categories based on how they form.
Igneous rocks form when molten rock (magma or lava) cools and solidifies. When magma cools beneath the surface, it creates intrusive igneous rocks like granite. When lava cools on the surface, it forms extrusive igneous rocks like basalt, pumice, and obsidian.
Sedimentary rocks form through lithification—the compaction and cementation of sediments. These rocks, including sandstone, limestone, and shale, are where fossils are commonly found since they form in environments where plants and animals can be preserved.
Metamorphic rocks result from the recrystallization of existing rocks under intense heat and pressure, which changes their mineral composition. Examples include marble, slate, and quartzite. Regional metamorphism often creates foliation—thin sheets within the rock that form along parallel planes.
💡 The rock cycle connects all three rock types in a continuous process. Rocks don't stay in one form forever—they transform from one type to another as they experience different environmental conditions over millions of years!
Minerals are naturally occurring, inorganic crystalline materials with unique chemical compositions. You can identify minerals by examining their properties, including
Their hardness (resistance to scratching) is measured on the Mohs scale from 1 (talc, very soft) to 10 (diamond, extremely hard). Other key properties include cleavage (how they break along weakness lines), luster (how they reflect light), and streak (the color of their powder form).
Weathering breaks down rocks and minerals through two main processes. Physical weathering breaks rocks apart without changing their chemical makeup. This happens through frost wedging (water freezing in cracks), salt cracking, abrasion (rocks grinding against each other), and even plant roots growing into cracks.
Chemical weathering alters rocks through chemical reactions. This includes oxidation (when iron in rocks reacts with oxygen), dissolution in water, and reactions with acids and bases in rainwater. These processes gradually transform even the hardest rocks into smaller particles.
🔍 The next time you find a rock or mineral, try testing its properties! Scratch it with different objects to estimate its hardness, or rub it on a rough surface to see its streak color.
Soil is the loose, weathered material that covers much of Earth's surface. It varies tremendously in depth, composition, color, and texture depending on climate, parent material, and age.
Four main soil types exist, each with unique properties. Clay soil packs tightly and holds water well, while sandy soil has sharp edges and drains quickly but holds few nutrients. Silt soil feels smooth when wet but not as sticky as clay. Loam soil—a balanced mixture of clay, silt, sand, bacteria, water, and humus—is ideal for plant growth.
Soil forms distinct horizontal layers called horizons. The topmost layer contains organic debris (O horizon), followed by topsoil that mixes minerals with organic material (A horizon). Below this is subsoil where compounds from above accumulate (B horizon), then partially weathered parent material (C horizon), with solid bedrock (R horizon) at the bottom.
🌱 The next time you're outside, dig a small hole and examine the soil layers. The color changes between horizons can tell you a lot about what's happening below your feet!
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.
You can download the app in the Google Play Store and in the Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
7
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Middle School Earth and space science 6th 7th 8th grade weathering and erosion
Earth and Space ScienceUnderstand physical and chemical weathering, and factors that affect weathering
Earth and Space ScienceThis talks about mechanical weathering, chemical weathering, rate of weathering and characteristics of soil.
Earth and Space ScienceApp 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
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
Rocks, minerals, and soil form the foundation of Earth's crust and are essential to understanding our planet. These natural materials undergo fascinating transformations through various processes like heat, pressure, and weathering that shape the Earth's surface over time.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Rocks are solid materials formed through three main processes: heat, pressure, or layering. They fall into three major categories based on how they form.
Igneous rocks form when molten rock (magma or lava) cools and solidifies. When magma cools beneath the surface, it creates intrusive igneous rocks like granite. When lava cools on the surface, it forms extrusive igneous rocks like basalt, pumice, and obsidian.
Sedimentary rocks form through lithification—the compaction and cementation of sediments. These rocks, including sandstone, limestone, and shale, are where fossils are commonly found since they form in environments where plants and animals can be preserved.
Metamorphic rocks result from the recrystallization of existing rocks under intense heat and pressure, which changes their mineral composition. Examples include marble, slate, and quartzite. Regional metamorphism often creates foliation—thin sheets within the rock that form along parallel planes.
💡 The rock cycle connects all three rock types in a continuous process. Rocks don't stay in one form forever—they transform from one type to another as they experience different environmental conditions over millions of years!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Minerals are naturally occurring, inorganic crystalline materials with unique chemical compositions. You can identify minerals by examining their properties, including:
Their hardness (resistance to scratching) is measured on the Mohs scale from 1 (talc, very soft) to 10 (diamond, extremely hard). Other key properties include cleavage (how they break along weakness lines), luster (how they reflect light), and streak (the color of their powder form).
Weathering breaks down rocks and minerals through two main processes. Physical weathering breaks rocks apart without changing their chemical makeup. This happens through frost wedging (water freezing in cracks), salt cracking, abrasion (rocks grinding against each other), and even plant roots growing into cracks.
Chemical weathering alters rocks through chemical reactions. This includes oxidation (when iron in rocks reacts with oxygen), dissolution in water, and reactions with acids and bases in rainwater. These processes gradually transform even the hardest rocks into smaller particles.
🔍 The next time you find a rock or mineral, try testing its properties! Scratch it with different objects to estimate its hardness, or rub it on a rough surface to see its streak color.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Soil is the loose, weathered material that covers much of Earth's surface. It varies tremendously in depth, composition, color, and texture depending on climate, parent material, and age.
Four main soil types exist, each with unique properties. Clay soil packs tightly and holds water well, while sandy soil has sharp edges and drains quickly but holds few nutrients. Silt soil feels smooth when wet but not as sticky as clay. Loam soil—a balanced mixture of clay, silt, sand, bacteria, water, and humus—is ideal for plant growth.
Soil forms distinct horizontal layers called horizons. The topmost layer contains organic debris (O horizon), followed by topsoil that mixes minerals with organic material (A horizon). Below this is subsoil where compounds from above accumulate (B horizon), then partially weathered parent material (C horizon), with solid bedrock (R horizon) at the bottom.
🌱 The next time you're outside, dig a small hole and examine the soil layers. The color changes between horizons can tell you a lot about what's happening below your feet!
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.
You can download the app in the Google Play Store and in the Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
7
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Middle School Earth and space science 6th 7th 8th grade weathering and erosion
Earth and Space ScienceUnderstand physical and chemical weathering, and factors that affect weathering
Earth and Space ScienceThis talks about mechanical weathering, chemical weathering, rate of weathering and characteristics of soil.
Earth and Space ScienceApp 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
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
