\(Đặt:n_{CO\left(p.ứ\right)}=a\left(mol\right)\left(a>0\right)\\PTHH:FeO+CO\rightarrow \left(t^o\right)Fe+CO_2\\ Fe_2O_3+3CO\rightarrow\left(t^o\right)2Fe+3CO_2\\ hh.khí:CO\left(dư\right),CO_2\\ n_{CO_2}=n_{CO\left(p.ứ\right)}=a\left(mol\right)\\ m_{hh.khí}=18\left(g\right)\\ \Leftrightarrow28.\left(0,5-a\right)+44a=18\\ \Leftrightarrow a=0,25\left(mol\right)\\ \Rightarrow X:\%m_{CO_2}=\dfrac{0,25.44}{18}.100\%\approx61,111\%\\ \Rightarrow\%m_{CO\left(dư\right)}\approx38,889\%\\ b,m_{Fe}=m_{oxit}+m_{CO\left(p.ứ\right)}-m_{CO_2}=15,2+0,25.28-0,25.44=11,2\left(g\right)\\ Đặt:n_{FeO}=t\left(mol\right);n_{Fe_2O_3}=n\left(mol\right)\)
\(\Rightarrow\left\{{}\begin{matrix}72t+160n=15,2\\t+3n=0,25\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}t=0,1\\n=0,05\end{matrix}\right.\\ \Rightarrow m_{FeO}=72t=7,2\left(g\right);m_{Fe_2O_3}=160n=8\left(g\right)\)