posted by mohd .
A 1.362 g sample of an iron ore that contained Fe_3O_4 was dissolved in acid and all the iron was reduced to Fe^2+. the solution was then acidified with H_2SO_4 and titrated with 39.42 mL of 0.0281 M KMnO_4 , which oxidized the iron to Fe^3+.
Net ionic equation
a) what was the percentage by mass of iron in the ore?
b) what was the percentage by mass of Fe_3O_5 in the or
There is a chemist around but how would he know to read this?