Đặt :
nFeO (bđ) = a (mol)
nZnO ( bđ) = b (mol)
=> mhh = 72a + 81b = 15.3 (g) (1)
FeO + H2 -to-> Fe + H2O
ZnO + H2 -to-> Zn + H2O
m chất rắn = mFeO dư + mZnO dư + mFe + mZn
=> 0.2a*72 + 0.2b*81 + 56*0.8a + 65*0.8b = 12.74
=> 59.2a + 68.2b = 12.74 (2)
(1) , (2) :
a = b = 0.1
%FeO = 0.1*72/15.3 * 100% = 47.06%
%ZnO = 100 - 47.06 = 52.94%