3 years ago

Which one is a chemical reaction? Why?

Chemistry

1 answer:

Alex17521 [72]3 years ago

3 0

Answer:

Copper turns green on exposure to air

Explanation:

Liquid water freezes to form ice: Physical change

Reason: Water can melt back when it becomes ice.

Copper turns green on exposure to air: Chemical change

Reason: The copper can not change back from the green state when it turns green.

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