❓ why
Why does copper turn green over time?
Quick Answer
Copper forms a green patina when it reacts with oxygen, carbon dioxide, and moisture. The surface becomes coated with stable copper compounds that protect the metal underneath.
The Full Story
Bare copper first oxidizes to form reddish-brown copper oxide, and over time it can react further with carbon dioxide, water, and atmospheric pollutants. This produces a green surface layer known as patina, often containing compounds such as copper carbonates and copper sulfates. The Statue of Liberty is green for this reason. The patina is actually protective, slowing deeper corrosion instead of damaging the metal further.
Key Facts
1.Copper is element 29
2.The green coating is called patina
3.The Statue of Liberty’s color came from natural weathering
YouTube Angle
Suggested video title for this topic:
"How a reddish metal slowly becomes iconic green."
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