Answer:
6.25 x 10^-4 moles H2O
Step-by-step explanation:
moles H2O = 10 x 10^-3 g O2 x (1 mol O2/MM O2) x (2 moles H2O/ 1 mol O2) =
= (10^-2 / 32) x 2 = 6.25 x 10^-4 moles H2O
conversion factor 2moles H2O = 1 mol O2
MM O2 = 32g/mol
mass O2 = 10 mg = 10 x 10^-3 g