The photosynthesis reaction uses six oxygen atoms in the form of six water molecules (H₂O).

Here's the overall equation for photosynthesis:

6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂

* 6CO₂: Six molecules of carbon dioxide

* 6H₂O: Six molecules of water (containing the six oxygen atoms)

* C₆H₁₂O₆: One molecule of glucose (sugar)

* 6O₂: Six molecules of oxygen (released as a byproduct)

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