# What is the mass of 0.7891 mol of ferric oxide (Fe_2O_3)?

$F {e}_{2} {O}_{3}$ has a formula mass of $159.69 \cdot g \cdot m o {l}^{-} 1$.
$159.69 \cdot g \cdot m o {l}^{-} 1 \times 0.7891 \cdot m o l$ $\cong$ $128 \cdot g$.