<u>We want the molar mass (gfm) of Fe and FeS.</u>
Fe = 55.8 g/mol and FeS = 87.8 g/mol (55.8 +32.0).
<u>Explanation:</u>
We want ratio between Fe:FeS 8:8. This comes from the coefficients of the equal chemical equation.
Now we set up conversion factors following the roadmap from above.
Unit we want in the numerator, unit to cancel in the denominator.
Multiply the numerators, and divide the denominators.
The outcome is 243.82 g of ferrous sulphite
By the above given formula we can find any amount of Fes produced by any amount of ferrous react with sulphite.