A sample of hydrated oxalic acid, H₂C₂O₄· xH₂O, has a mass of 0.630 g…

A sample of hydrated oxalic acid, $\text{H}_{2}\text{C}_{2}\text{O}_{4}\cdot \text{xH}_{2}\text{O}$, has a mass of 0.630 g. It is dissolved and made up to 100.0 mL. A portion of 10.0 mL, acidified and warmed, is titrated with $0.0200\ \text{mol/L}$ potassium permanganate, and 10.0 mL is needed. Use H = 1, C = 12 and O = 16 in g/mol, so that anhydrous oxalic acid is $90\ \text{g/mol}$. Find the amount of permanganate used, the amount of oxalic acid in the portion, the molar mass of the hydrate, and the value of $x$.