Apotential source of error for this lab could arise if not enough acid was added to the iron solution before the titration was started. this would allow much of permanganate to go to mno2 rather then mn 2 . how would this affect the % of iron found at the end of the experiment

The manganese (II) oxide will act as a contaminant affecting the iron final result.

Explanation:

Hello,

In this case, a typical case in which a solution containing iron is titrated with potassium permanganate to oxidize the iron and consequently reduce the manganese into the permanganate. In such a way, by cause of the lack of acid, when manganese dioxide, is produced instead of manganese (II) ions, , such oxide will act as a contaminant in the final product collection, affecting the experiment reliability when finding the iron, that is why we must assure the total reduction to manganese (II) ions.

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