1. Write the balanced chemical equation:

2H₂ + O₂ → 2H₂O

2. Mole Ratios:

This balanced equation tells us the following mole ratios:

* 2 moles of H₂ react with 1 mole of O₂

* 2 moles of H₂O are produced from 1 mole of O₂

3. Calculation:

Since you have 1 mole of O₂, you will need:

* 1 mole O₂ * (2 moles H₂ / 1 mole O₂) = 2 moles of H₂

And you will produce:

* 1 mole O₂ * (2 moles H₂O / 1 mole O₂) = 2 moles of H₂O

Answer:

* You would need 2 moles of hydrogen (H₂) to react completely with 1 mole of oxygen (O₂).

* This reaction would produce 2 moles of water (H₂O).