Final answer:
O₂ in the equation represents molecular oxygen, which is produced when hydrogen peroxide (H₂O₂) decomposes to yield water (H₂O) and oxygen (O₂) in a stoichiometric ratio.
Step-by-step explanation:
In the chemical equation 2H₂O₂ → 2H₂O + O₂, the O₂ represents molecular oxygen. Molecular oxygen consists of two oxygen atoms bonded together and is a product of the decomposition of hydrogen peroxide (H₂O₂).
The decomposition reaction liberates molecular oxygen and water, and when balanced, it shows that two moles of hydrogen peroxide produce one mole of oxygen and two moles of water. This stoichiometric relationship indicates that for every two molecules of hydrogen peroxide that decompose, one molecule of oxygen and two molecules of water are produced.