Top 10 CHEMISTRY grade 7-9 skills and popular lessons

Chemistry rocks!
+5 votes
1 lesson
Lesson created In 7-9 by Helen Veerman Olympian (1.2k)  
Carbon atoms are unique because they can bond together to form very long, durable chains that can have branches or rings of various sizes and often contain thousands of carbon atoms. Its the glue of life!
+4 votes
2 lessons
Lesson created In 7-9 by Asher Streets Rockstar (4.6k)  
Learn how atoms form bonds with one another to create molecules...all due to the properties of electrons.
0 votes
1 lesson
Lesson created In 7-9 by Asher Streets Rockstar (4.6k)  
Seeing is believing! Learn how to interpret the equation PV=nRT into visual reality, developing a deep understanding and intuition about how changes in these 4 properties relate with one another.
0 votes
1 lesson
Lesson created In 7-9 by Asher Streets Rockstar (4.6k)  
Learn about dilutions with fun mixes you can try at home! Understand the key properties of Molarity and how to use the critical formula: M1V1 = M2V2.
+6 votes
1 lesson
Lesson created In 7-9 by Asher Streets Rockstar (4.6k)  

Using Kw, the dissociation constant for water, this video explains how acids and bases relate to the concentrations of H+ and OH-. The video talks through the critical features needed to understand acid and base chemistry, including how to calculate using logarithms.

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+5 votes
1 lesson
Lesson created In 7-9 by Erna Gold (880)  

Your entire digestive tract is less than 30 ft long. Your pancreas and your liver produce enzymes to help you break down food. The liver also works to detoxify your body, and can regenerate itself when up to ⅔ of it is lost. Fiber is indigestible, and is left over when all other nutrients are removed from food. Check out these fascinating videos about our great digestive system:

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