Given a scientific question and its correct answer, generate supporting facts for the answer. This supporting fact can be an explanation for the answer to the given question.

Q: Question: How does carbon dioxide chemically weather rocks? Answer: by creating acids

A: Carbon dioxide chemically weathers rock by creating acids.
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Q: Question: The other ammonium ions are changed into nitrogen gas by what? Answer: denitrifying bacteria

A: The other ammonium ions are changed into nitrogen gas by denitrifying bacteria.
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Q: Question: Fertilization occurs when an egg and sperm come together to form a what? Answer: zygote

A:
Fertilization occurs when an egg and sperm come together to form a zygote.
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