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Lesson 15 of 18

Checkpoint: metalloids, minerals, the acid test and matter

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5 min

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Four questions on the last four ideas. Feedback comes as you answer, and you can retry any time.

Silicon is a metalloid. Which of its test results matches copper?

What are most rocks made of?

Iron meets dilute hydrochloric acid. What do they make?

A balance shows that a thing has mass. What else must be true for it to be matter?

0 of 4 answered

Finish the checkpoint to complete this lesson — you can always retry for a better score.