Mystery #1Tier 2plastic oil chemistry
How does thick black oil from underground become a clear plastic bottle?
Oil that comes up from deep underground is thick, black and gloopy, nothing like the clear, light bottle in your lunchbox. Yet that bottle really was made from oil. Somehow the gloopy black stuff was turned into something hard and see-through. How does thick black oil from underground become a clear plastic bottle?

Your guess
What do you think turns runny oil into solid plastic?
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