A 46.9 g of iron ore is treated as follows. The iron in the sample is all converted by a series of chemical reactions to Fe2O3. The mass of Fe2O3 is measured to be 11.6 grams. What was the percent iron in the sample of ore?

Answer in units of %

1 answer

Convert 11.6 g Fe2O3 to g Fe. The easy way to do that is to multiply by a chemical factor which, which as far as I know, isn't taught anywhere in the world anymore anymore.
11.6 x (2*molar mass Fe/molar mass Fe2O3) = g Fe.
Then %Fe = (g Fe/mass ore sample)*100 = ??