Mass Conservation in Reactions
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Objective
I can explain how mass is conserved during chemical reactions.
Part 1 of 4
Warm-up video
Crash Course Kids · 4:09Vetted channel
We don't generate video — this one is by Crash Course Kids on YouTube. The practice questions and exit ticket below were drafted by AI for this objective, and every question is editable in the teacher guide.
Part 2 of 4
Key concepts
3 concepts
- 1
A physical change is a change in the shape or form of matter, but it does not create a new substance.
- 2
In a chemical reaction, the substances that react are called reactants, and the new substance that is made is called the product.
- 3
The conservation of mass states that matter is never made or lost, it only changes form.
Part 3 of 4
Practice
10 questions
Which principle states that the total mass within a closed system remains constant, irrespective of the processes occurring inside?
What is the main difference between a physical change and a chemical change, according to the video?
Part 4 of 4
Exit ticket
Quick comprehension check
“A student performs a chemical reaction in a closed container. Before the reaction, the total mass of the reactants is 100 grams. After the reaction, what should the total mass of the products be, according to the law of conservation of mass?”
Sample answer included in the free materials
Get the materials
Teacher guide, student handout, and slides — free, in Google Docs format
Teacher Guide
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