How many atoms of Fe are in 100g of FeS
I'm no expert in Chemistry, but I will give it a shot!
There is no such thing as FeS!, as far as I know. But, there is
FeSO4, (Iron(II) sulfate or Ferrous sulfate), which has a molecular weight of about 152 g/mol.
The ratio of Fe in FeSO4 =~56 / 152 =0.368421
1 mole of FeSO4 =6.0221415 x 10^23 atoms. But you have only 100 grams. So 100 / 152 =0.657895 of 1 mole of FeSO4 . So:
0.368421 x 0.657895 x 6.0221415 x 10^23 =1.46 x 10^23 atoms of Fe.
Note: Somebody should check this!.
Fe S is iron sulfide and has a molar mass 87.91 (Fe 55.845 S 32.06) 100g / (87.91g/mole) = # moles
1 Mole is 6.022 x 10^23 particles
100 / 87.91 x 6.022 x 10^23 = number of MOLECULES of FeS
EACH MOLECULE OF FeS has only one ATOM of Fe, so this is the number of Fe atoms.
Since FeS has TWO atoms for each MOLECULE:
The TOTAL number of ATOMS will be double this...... 100 / 87.91 x 6.022 x 10^23 x 2 = # atoms