Mass is Always Conserved
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Objective
I can explain how the law of conservation of mass applies to chemical and physical changes.
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, like sugar dissolving in water, and it does not create a new substance.
- 2
In a chemical reaction, the substances that react are called reactants, and the new substances that are formed are called products; for example, the ingredients in a cake are the reactants and the baked cake is the product.
- 3
The conservation of mass states that matter is never created or destroyed, but it can change forms, such as when water evaporates or when sugar dissolves in water.
Part 3 of 4
Practice
8 questions
Define the law of conservation of mass in your own words.
Give an example of a physical change. Explain how the law of conservation of mass applies to your example.
Part 4 of 4
Exit ticket
Quick comprehension check
“Explain how the law of conservation of mass applies when water evaporates from a glass. Be specific about what happens to the mass of the water and where it goes.”
Sample answer included in the free materials
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