The fire washing ore "PYROLUSITE" 
Pyrolusite ore, being an impure manganese (IV) oxide, can be used to obtain elemental manganese.
To analyse a pyrolusite ore for its manganese (IV) oxide content, a 0.4118 g sample is treated with 0.7938 g ethanedioic acid dihydrate in an acidic medium. Following this reaction, the excess ethanedioic acid is titrated with potassium permanganate solution (c = 0.050 mol/l), 14.40 ml of which being required.
- Describe a chemical procedure to derive manganese from pyrolusite using chemical equations as well as the English language.
- Develop net ionic equations for all described reactions in the text and calculate the mass percent of manganese (IV) oxide in the ore.
- Considering oxalic acid, a diprotic acid with pKa values of 1.25 and 4.275, calculate the pH increase of oxalic acid after its reaction with pyrolusite.
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