Chromium metal can be produced by the reduction of Cr2O3 with elemental silicon: 2 Cr2 O3 + 3 Si...

Below is the given balanced chemical equation:

{eq}2 Cr_2O_3 + 3 Si \rightarrow 4 Cr + 3 SiO_2 {/eq}

Below is the masses of components in the balanced chemical equation:

{eq}\\Cr_2O_3=304g \\Si=74g \\ Cr=208g {/eq}

Now,

304 g of Chromium oxide produces 208 g of Chromium metal,

350 g of Chromium oxide will produce {eq}\frac{208}{304} \times 350 \\ =239.5 g {/eq} of Chromium metal.

Now,

{eq}Percentage\,yield = \frac{Actual\,yield}{Theoretical\,yield} \times 100 {/eq}

Putting the values, we get

{eq}\\ Percentage\,yield = \frac{213.2}{239.5} \times 100 \\ Percentage\,yield = 89.02 \% {/eq}