Răspuns:
Explicație:
FeSO4
*raport atomic
Fe:S:O = 1:1:4
*masa moleculara=MFe+MS+4*MO=56+32+16*4=152
*raport de masa
56:32:64 (impartim cu 8) => 7:4:8
*compozitia procentuala
152g.........................................100%
56g..........................................x%
32g..........................................y%
64g..........................................z%
=>x=36.85% Fe
=>y=21,05% S
=>z= 42,1% O
