Mystery #1Tier 2acids / chemistry
Why does lemon juice make a dull old coin shiny?
Drop a dull, brownish copper coin into a little lemon juice for a few minutes and it comes out gleaming like new. You didn't scrub it. So what did the lemon actually do to the grime?
Your guess
What's your hunch about how sour lemon juice cleans a dull coin without any scrubbing?
There's no single magic word to type, have a go in your own words, then reveal the answer to see how close you got.
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