It's just a matter of converting the mass of one material to another.
mm stands for molar mass and am stands for atomic mass.
You want to convert 20.7 g Fe2O3 to mass Fe initially. How many mols Fe2O3 do you have?
mols Fe2O3 = grams Fe2O3/mm Fe2O3 = ?.
mols Fe = ? x (2 mol Fe/1 mol Fe2O3) = ?
g Fe = mols Fe x am Fe.
A 33.8 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 20.7 g.
What was the mass of iron in the sample of
ore?
Answer in units of g.
- I Don't Even Know Where To Start With This.
3 answers
mols Fe2O3= 20.7/159.7= 0.1296
mols Fe= 0.1296x2= 0.2592
g Fe= 0.2592x55.85 = 14.478334
? Thanks a bunch.
mols Fe= 0.1296x2= 0.2592
g Fe= 0.2592x55.85 = 14.478334
? Thanks a bunch.
That looks ok to me but you have too many digits in your answer. The 20.7 number limits the number of significant digits to three, therefore, your answered should be rounded to 14.5 g Fe.
3 answers