Răspuns:
A,Fe= 56g/mol
miu,FeO= 72g/mol
miuFe2O3= 160g/mol
consider amestecul format din a moli FeO SI b moli Fe2O3
IN 72a+160b,g, amestec......sunt 56a+ 112g, g Fe
100g..............................................................75g
75(72a+160b)=100(56a+112b)----> a/b= 800/200=4/1 raport molar
raportul masic m,FeO/m,Fe2O3= 4x72/1x160
=288/160= 9/5
Explicație: