12 tablets containing Fe(II) fumarate and inert binder are dissolved in 150 mL of 0.100 M HCl.

Fe(II) is oxidized to Fe(III) with an excess of H2O.

The gel is filtered and heated in a furnace to remove the water.

NH4OH is added to precipitate hydrous Fe(III) oxide (Fe2O3), as a gel.

A final mass of 0.2770 g was isolated at the end of the experiment.

What is the average mass of iron per tablet?
Answer: 16.14mgFe

Please explain the steps to get to this answer.