Oxygen and carbon dioxide

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Q1: What happens when there is too much carbon dioxide?

[Answer]

Oxygen combines with fuels and gives off heat very rapidly – this is burning. Oxygen combines with our food inside our bodies to release energy, too.

Carbon dioxide is needed by plants to breathe. But carbon dioxide also soaks up heat and so the more carbon dioxide there is in the air, the more the Earth's atmosphere heats up – this is bad news – it is called global warming.