A sample of an arsenic compound weighing 0.1023 g was dissolved and all the arsenic converted to arsenic in the +3 oxidation state. A 0.0250 M solution of an acidified permanganate (MnO4-), was added, which oxidized the arsenic to the +5 oxidation state. The manganese was reduced to the +2 state. If it took 10.64 mL of the permanganate solution to exactly react with the arsenic, what is the percentage of arsenic in the sample?
a) 42.5
b) 47.8
c) 7.79
d) 19.5
e) 48.7