FeSO4
raport de masa=r . m.
r. m .=AFe : A S: 4AO=56: 32 : 4.16=56 : 32: 64 =7 : 4 :8
Comp. procentuala prin masa moleculara
M=56 + 32 +64=152 ----->1 mol=152 g
152g FeSO4--------56 g Fe--------32g S-----------64 g O
100 g-----------------------x---------------y-------------------z
x=100 .56:152=36,84 la suta Fe
y=100.32:152=
z=100.64:152=
Continua !