Permanganate, iron ions reacting with

The iron content of ores can be determined by titrating a sample with a solution of potassium permanganate, KMn04. The ore is dissolved in hydrochloric acid, forming iron(II) ions, which react with Mn04 ... 

The ferrous ion, c1+(aq), reacts with the permanganate ion, Mn04 (ag), in an acidic solution to produce the ferric ion, Fe3+(ag). A 6.893-gram sample of ore was mechanically crushed and then treated with concentrated hydrochloric acid, which oxidized all of the iron in the ore to the ferrous ion, Fe2+(aq). Next, the acid solution containing all of the ferrous ions was titrated with 0.100 M KMn04 solution. The end point was reached when 13.889 mL of the potassium permanganate solution was used. 

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