Answer:
According to the reaction stoichiometry, 1 mole of P4010 reacts with 6 moles of H2O to produce 4 moles of H3PO4. Therefore, we can use a proportion to calculate the moles of H3PO4 produced from 8.0 moles of H2O:
$\frac{4 \text{ mol H3PO4}}{6 \text{ mol H2O}} = \frac{x \text{ mol H3PO4}}{8.0 \text{ mol H2O}}$
Solving for $x$, we get:
$x = \frac{4 \text{ mol H3PO4}}{6 \text{ mol H2O}} \times 8.0 \text{ mol H2O} = 5.3 \text{ mol H3PO4}$
Therefore, 5.3 moles of H3PO4 form from 8.0 moles of H2O.