posted by Emily on .
A 12.8 g sample 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 21.3 g.
What was the mass of iron in the sample of
Answer in units of g
21.3 g Fe2O3 x (1 mol Fe2O3/molar mass Fe2O3) x (2 mol Fe/1 mol Fe2O3) x (atomic mass Fe/1 mol Fe) = g Fe
Note: There is an easier way to do this if you use the chemical factor; however, schools don't teach that anymore.
21.3 x *(2Fe/Fe2O3) = 21.3 x (2*55.85/159.6) = ? g Fe.