A 0535 G Sample of Pyrolusite Ore (Impure MnO₂)is Treated with with 1.42

Multiple Choice

A 0.535 g sample of pyrolusite ore (impure MnO₂) is treated with 1.42 g oxalic acid (H₂C₂O₄ ∙ 2H₂O) in an acidic medium.Following this reaction,the excess oxalic acid is titrated with 0.1000 M KMnO₄,36.6 mL being required.What is the % MnO₂ in the ore? The reactions are:
H₂C₂O₄ ∙ 2 H₂O(aq) + MnO₂(s) + 2 H⁺(aq) → Mn²⁺(aq) + 4 H₂O(l) + 2 CO₂(g)
5 H₂C₂O₄ ∙ 2H₂O(aq) + 2 MnO₄^-(aq) + 6 H⁺(aq) → 2 Mn²⁺(aq) + 18 H₂O(l) + 10 CO₂(g)

A) 34.4%
B) 61.1%
C) 2.33%
D) 1.22%
E) 38.9%