Answer:
1 Mole O₂ / 2 Mole H₂O
Explanation:
The balance chemical equation for the synthesis of water is as follow,
2 H₂ + O₂ → 2 H₂O
In this equation the moles are specified by the coefficients i.e.
2 moles of H₂ reacting with 1 mole of O₂
2 moles of H₂ producing 2 moles of H₂O
1 mole of O₂ producing 2 moles of H₂O
Hence the molar ratio for O₂ and H₂O can be written as,
1 Mole O₂ : 2 Mole H₂O
or,
1 Mole O₂ / 2 Mole H₂O