Consider the following reaction
$$\ce{4H2O + 5I2O4 -> 8HIO3 + I2}$$
If 0.167 mol of $\ce{H2O}$ is added to 0.200 mol of $\ce{I2O4}$ what amount (moles) of $\ce{HIO3}$ can be formed, it the reaction goes to completion?
(A) 0.084 mol
(B) 0.125 mol
(C) 0.320 mol
(D) 0.334 mol
Can someone please explain the answer to this problem. I have been at it for ages and keep coming up with an answer close to C but not close enough to count it! Help!