How many moles of oxygen gas are needed to produce 2.14 moles of water?

Answer 1

The balanced reaction is 2 H₂ + O₂ --> 2 H₂O. Every one mole of oxygen gas produces two moles of water, so 1/2 (2.14) = 1.07 moles of O₂ produces 2.14 moles of H₂O.