Answer:
The mole ratio of PbO2 to H2O is 1 : 2.
Step-by-step explanation:
The balanced reaction equation is:
Pb + PbO2 + 2H2SO4 → 2PbSO4 + 2H2O
On the reactant side, we have 1 mole of Pb, 1 mole of PbO2, 2 moles of H2SO4.
On the product side, we have 2 moles of PbSO4 and 2 moles of H2O.
This means that for ever 1 mole of PbO2 consumed, 2 moles of water is formed as product.
Hence, the mole ratio of PbO2 to H2O is 1 : 2.