Question

3. Ethan is heating a substance and observes that it turns from a brown solid to a black powder. He then compares the properties of each and finds they are different. Which option below best summarizes Ethan's observation?
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1 point
A. The brown solid changed color and size when he added heat, so he observed a physical change.
B. The brown solid became a new substance when he added heat, so he observed a physical change.
C. The brown solid became a new substance when he added heat, so he observed a chemical change.
D. The brown solid changed color when he added heat, so he observed matter being destroyed by a chemical change.
Option 5

Answer 1

C. The brown solid becoming a black powder with different properties indicates a chemical change (a new substance formed). Options A and B are wrong because a change of substance is a chemical, not a physical, change; D is wrong because chemical changes do not destroy matter.