<u>Answer:</u>
<u>For 1:</u> The amount of potassium iodate that were titrated is
moles
<u>For 2:</u> The amount of sodium thiosulfate required is
moles
<u>Explanation:</u>
To calculate the number of moles for given molarity, we use the equation:

Molarity of
solution = 0.0100 M
Volume of solution = 25 mL
Putting values in above equation, we get:

Hence, the amount of potassium iodate that were titrated is
moles
The chemical equation for the reaction of potassium iodate and sodium thiosulfate follows:

By Stoichiometry of the reaction:
2 moles of potassium iodate reacts with 1 mole of sodium thiosulfate
So, 0.00025 moles of potassium iodate will react with =
of sodium thiosulfate
Hence, the amount of sodium thiosulfate required is
moles