Khan Academy is a nonprofit providing a free, world-class education for anyone, anywhere. Our interactive practice problems, articles, and videos help students succeed in math, biology, chemistry, physics, history, economics, finance, grammar, and many other topics. Khan Academy provides teachers with data on how their students are doing so they can identify gaps in learning and provide tailored instruction. We also offer free personalized SAT and LSAT practice in partnership with the College Board and the Law School Admission Council. Our resources have been translated into dozens of languages, and 15 million people around the globe learn on Khan Academy each month. Want to extend your learning beyond YouTube? Practice what you've just discovered for free: www.khanacademy.org
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Courses on Khan Academy are always 100% free. Start practicing—and saving your progress—now!
Our new middle school chemistry course launches in July 2025, but we couldn’t wait to share it! Videos like this one are rolling out over the next few months to give you a sneak peek of what’s to come. 🧪💡
Want to explore more? Check out the full middle school playlist here:
https://www.youtube.com/playlist?list=PLSQl0a2vh4HBnhjPgsJU2y1UhMwcYmb5u
Properties are characteristics that define substances, helping us differentiate them. Physical properties, like color, density, and magnetism, can be observed or measured without changing the substance. These properties are further classified into intrinsic (independent of size, like color) and extrinsic (size-dependent, like mass). Understanding these helps identify and describe materials effectively.
00:00 What are properties?
02:56 What are physical properties?
04:42 Intrinsic & extrinsic properties
06:11 Summary
Khan Academy is a nonprofit organization with the mission of providing a free, world-class education for anyone, anywhere. We offer quizzes, questions, instructional videos, and articles on a range of academic subjects, including math, biology, chemistry, physics, history, economics, finance, grammar, preschool learning, and more. We provide teachers with tools and data so they can help their students develop the skills, habits, and mindsets for success in school and beyond. Khan Academy has been translated into dozens of languages, and 15 million people around the globe learn on Khan Academy every month. As a 501(c)(3) nonprofit organization, we would love your help!
Donate or volunteer today! Donate here: https://donate.khanacademy.org/give/419869/#!/donation/checkout
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Teachers, say goodbye to bulky lesson plans and hello to more time for your students.! 🎉
Khanmigo's Lesson Planner just got a HUGE upgrade! You can create 5-part, 5E, Inquiry-Based, and UDL lesson plans in minutes. We're working on more access, but creating a "high-detail" lesson plan is only available using the 5-part lesson planning function. Let us know how you use Khanmigo to lesson plan in the comments below!
Learn more and start using Khanmigo for free today at bit.ly/3Qp7TyH
See how she brings AI-powered support into her classroom. Thanks for sharing, Miss Clarke! 🙌
🔗 Want to try it yourself? Sign up for free: https://www.khanacademy.org/teacher/khanmigo-tools/blooket-generator?platform=KhanAcademy&utm_source=youtube_shorts&utm_medium=social&utm_campaign=blooket
What do you do when you can't break down an unfamiliar word? Look at its neighbors! David walks through a process for determining the meaning of a word he's never seen before.
Courses on Khan Academy are always 100% free. Start practicing—and saving your progress—now!
Khan Academy is a nonprofit organization with the mission of providing a free, world-class education for anyone, anywhere. We offer quizzes, questions, instructional videos, and articles on a range of academic subjects, including math, biology, chemistry, physics, history, economics, finance, grammar, preschool learning, and more. We provide teachers with tools and data so they can help their students develop the skills, habits, and mindsets for success in school and beyond. Khan Academy has been translated into dozens of languages, and 15 million people around the globe learn on Khan Academy every month. As a 501(c)(3) nonprofit organization, we would love your help!
Donate or volunteer today! Donate here: https://www.khanacademy.org/donate?utm_source=youtube&utm_medium=desc
Volunteer here: https://www.khanacademy.org/contribute?utm_source=youtube&utm_medium=desc
Image credit: https://en.wikipedia.org/wiki/Carabiner#/media/File:Benutzung_eines_Karabiners.gif
With the help of the friendly Australian wombat, David demonstrates how to make an inference while reading informational text.
Courses on Khan Academy are always 100% free. Start practicing—and saving your progress—now!
Khan Academy is a nonprofit organization with the mission of providing a free, world-class education for anyone, anywhere. We offer quizzes, questions, instructional videos, and articles on a range of academic subjects, including math, biology, chemistry, physics, history, economics, finance, grammar, preschool learning, and more. We provide teachers with tools and data so they can help their students develop the skills, habits, and mindsets for success in school and beyond. Khan Academy has been translated into dozens of languages, and 15 million people around the globe learn on Khan Academy every month. As a 501(c)(3) nonprofit organization, we would love your help!
Donate or volunteer today! Donate here: https://www.khanacademy.org/donate?utm_source=youtube&utm_medium=desc
Volunteer here: https://www.khanacademy.org/contribute?utm_source=youtube&utm_medium=desc
Courses on Khan Academy are always 100% free. Start practicing—and saving your progress—now!
Our new middle school chemistry course launches in July 2025, but we couldn’t wait to share it! Videos like this one are rolling out over the next few months to give you a sneak peek of what’s to come. 🧪💡
Want to explore more? Check out the full middle school playlist here:
https://www.youtube.com/playlist?list=PLSQl0a2vh4HBnhjPgsJU2y1UhMwcYmb5u
A mixture is a physical blend of two or more substances, unlike pure substances such as elements or compounds. Homogeneous mixtures are uniform throughout, with components evenly distributed at a molecular level, while heterogeneous mixtures have visible separation between components. Physical properties like density or solubility allow separation without a chemical reaction. Examples include salt water (homogeneous) and oil and water (heterogeneous).
00:00 Intro
00:29 Elements, Compounds & Mixtures
01:37 Difference between compounds & mixtures
02:32 Homogeneous mixtures
03:18 Heterogeneous mixtures
03:58 Identifying the type of mixture
05:15 Summary
Khan Academy is a nonprofit organization with the mission of providing a free, world-class education for anyone, anywhere. We offer quizzes, questions, instructional videos, and articles on a range of academic subjects, including math, biology, chemistry, physics, history, economics, finance, grammar, preschool learning, and more. We provide teachers with tools and data so they can help their students develop the skills, habits, and mindsets for success in school and beyond. Khan Academy has been translated into dozens of languages, and 15 million people around the globe learn on Khan Academy every month. As a 501(c)(3) nonprofit organization, we would love your help!
Donate or volunteer today! Donate here: https://donate.khanacademy.org/give/419869/#!/donation/checkout
Volunteer here: https://www.khanacademy.org/contribute?utm_source=youtube&utm_medium=desc
Courses on Khan Academy are always 100% free. Start practicing—and saving your progress—now!
Our new middle school chemistry course launches in July 2025, but we couldn’t wait to share it! Videos like this one are rolling out over the next few months to give you a sneak peek of what’s to come. 🧪💡
Want to explore more? Check out the full middle school playlist here:
https://www.youtube.com/playlist?list=PLSQl0a2vh4HBnhjPgsJU2y1UhMwcYmb5u
Homogeneous mixtures, also known as solutions, have components that are evenly distributed at the molecular level without chemical bonding. Examples include salt water, air, and alloys like steel. Solutions consist of a solute dissolved in a solvent, and their properties can vary with concentration. Mixtures can be separated using physical properties, such as boiling points or magnetism, unlike compounds that require chemical changes to be separated.
00:00 Intro
00:15 Analyzing salt water
02:36 Understanding solutions
03:54 Concentration of solutions
04:58 Summary
Khan Academy is a nonprofit organization with the mission of providing a free, world-class education for anyone, anywhere. We offer quizzes, questions, instructional videos, and articles on a range of academic subjects, including math, biology, chemistry, physics, history, economics, finance, grammar, preschool learning, and more. We provide teachers with tools and data so they can help their students develop the skills, habits, and mindsets for success in school and beyond. Khan Academy has been translated into dozens of languages, and 15 million people around the globe learn on Khan Academy every month. As a 501(c)(3) nonprofit organization, we would love your help!
Donate or volunteer today! Donate here: https://donate.khanacademy.org/give/419869/#!/donation/checkout
Volunteer here: https://www.khanacademy.org/contribute?utm_source=youtube&utm_medium=desc
Courses on Khan Academy are always 100% free. Start practicing—and saving your progress—now!
Our new middle school chemistry course launches in July 2025, but we couldn’t wait to share it! Videos like this one are rolling out over the next few months to give you a sneak peek of what’s to come. 🧪💡
Want to explore more? Check out the full middle school playlist here:
https://www.youtube.com/playlist?list=PLSQl0a2vh4HBnhjPgsJU2y1UhMwcYmb5u
Elements and compounds can exist as pure substances, each with a fixed, definite composition. Some compounds, like water, are made of individual molecules. Others, like salt, form crystals—large, repeating 3D patterns without individual molecules. Additionally, some elements pair up as diatomic molecules, such as O₂ and H₂, rather than existing as single atoms. Understanding whether a substance is molecular or crystalline and how diatomic elements differ from compounds is key to classifying matter.
00:00 Intro
00:48 What are crystals?
01:50 Chemical formula of crystals
03:29 General types of compounds
04:03 Diatomic elements
05:11 Summary of pure substances
Khan Academy is a nonprofit organization with the mission of providing a free, world-class education for anyone, anywhere. We offer quizzes, questions, instructional videos, and articles on a range of academic subjects, including math, biology, chemistry, physics, history, economics, finance, grammar, preschool learning, and more. We provide teachers with tools and data so they can help their students develop the skills, habits, and mindsets for success in school and beyond. Khan Academy has been translated into dozens of languages, and 15 million people around the globe learn on Khan Academy every month. As a 501(c)(3) nonprofit organization, we would love your help!
Donate or volunteer today! Donate here: https://donate.khanacademy.org/give/419869/#!/donation/checkout
Volunteer here: https://www.khanacademy.org/contribute?utm_source=youtube&utm_medium=desc
David explains what words are made of—yes, letters, sure! But also WORD PARTS! Learn about prefixes, roots, and suffixes and how they make meaning.
Courses on Khan Academy are always 100% free. Start practicing—and saving your progress—now!
Khan Academy is a nonprofit organization with the mission of providing a free, world-class education for anyone, anywhere. We offer quizzes, questions, instructional videos, and articles on a range of academic subjects, including math, biology, chemistry, physics, history, economics, finance, grammar, preschool learning, and more. We provide teachers with tools and data so they can help their students develop the skills, habits, and mindsets for success in school and beyond. Khan Academy has been translated into dozens of languages, and 15 million people around the globe learn on Khan Academy every month. As a 501(c)(3) nonprofit organization, we would love your help!
Donate or volunteer today! Donate here: https://www.khanacademy.org/donate?utm_source=youtube&utm_medium=desc
Volunteer here: https://www.khanacademy.org/contribute?utm_source=youtube&utm_medium=desc
Courses on Khan Academy are always 100% free. Start practicing—and saving your progress—now!
Our new middle school chemistry course launches in July 2025, but we couldn’t wait to share it! Videos like this one are rolling out over the next few months to give you a sneak peek of what’s to come. 🧪💡
Want to explore more? Check out the full middle school playlist here:
https://www.youtube.com/playlist?list=PLSQl0a2vh4HBnhjPgsJU2y1UhMwcYmb5u
Some substances, like copper or gold, are pure elements. Others, like water (H₂O), are compounds—made from two or more elements in fixed ratios, chemically bonded. Each compound has a unique formula, like CO₂ for carbon dioxide, representing its specific atomic arrangement. Compounds form molecules, tightly bonded units, creating an incredible diversity of substances in nature.
00:00 Intro
00:30 Compounds & elements
01:40 Compounds & molecules
03:00 More examples of compounds
03:58 Chemical formulas of compounds
05:36 Summary
Khan Academy is a nonprofit organization with the mission of providing a free, world-class education for anyone, anywhere. We offer quizzes, questions, instructional videos, and articles on a range of academic subjects, including math, biology, chemistry, physics, history, economics, finance, grammar, preschool learning, and more. We provide teachers with tools and data so they can help their students develop the skills, habits, and mindsets for success in school and beyond. Khan Academy has been translated into dozens of languages, and 15 million people around the globe learn on Khan Academy every month. As a 501(c)(3) nonprofit organization, we would love your help!
Donate or volunteer today! Donate here: https://donate.khanacademy.org/give/419869/#!/donation/checkout
Volunteer here: https://www.khanacademy.org/contribute?utm_source=youtube&utm_medium=desc
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