3H2(g)+Fe2O3(s)=2Fe(s)+3H2O(g)△H2
2Fe(s)+ O2(g)=Fe2O3(s)△H3
2Al(s)+ O2(g)=Al2O3(s)△H4
2Al(s)+Fe2O3(s)=Al2O3(s)+2Fe(s)△H5
下列关于上述反应焓变的判断正确的是( )