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Science | Physical Science | Chemical Elements

Chemical elements are substances composed of only one type of atom and they cannot be broken down further. Chemical elements are the simplest forms of matter and each one is assigned a specific atomic number. Check out these articles on chemical elements.

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Is it harmful to breathe 100-percent oxygen?

We need oxygen to live, so it seems to me that if we got more oxygen, we would be better off. Is it harmful to breathe 100-percent oxygen? What will happen?