\(CuO+H_2SO_4\rightarrow CuSO_4+H_2O\)
\(Fe_2O_3+3H_2SO_4\rightarrow Fe_2\left(SO_4\right)_3+3H_2O\)
Ta có: 80nCuO + 160nFe2O3 = 24 (1)
\(n_{H_2SO_4}=0,2.2=0,4\left(mol\right)\)
Theo PT: \(n_{H_2SO_4}=n_{CuO}+3n_{Fe_2O_3}=0,4\left(2\right)\)
Từ (1) và (2) ⇒ nCuO = nFe2O3 = 0,1 (mol)
⇒ mCuO = 0,1.80 = 8 (g)
mFe2O3 = 0,1.160 = 16 (g)
\(n_{CuO}=a\left(mol\right);n_{Fe_2O_3}=b\left(mol\right)\left(a,b>0\right)\\ CuO+H_2SO_4\rightarrow CuSO_4+H_2O\\ Fe_2O_3+3H_2SO_4\rightarrow Fe_2\left(SO_4\right)_3+3H_2O\\ \Rightarrow\left\{{}\begin{matrix}80a+160b=24\\a+3b=2.0,2=0,4\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}a=0,1\\b=0,1\end{matrix}\right.\\ \%m_{CuO}=\dfrac{0,1.80}{24}.100\%\approx33,333\%;\%m_{Fe_2O_3}=\dfrac{160.0,1}{24}.100\%\approx66,667\%\)
đổi `200ml=0,2l`
`=>n_(H_2 SO_4)=C_M *V=2*0,2=0,4(mol)`
gọi: \(\left\{{}\begin{matrix}n_{CuO}=a\left(mol\right)\\n_{Fe_2O_3}=b\left(mol\right)\end{matrix}\right.\)
\(PTHH:CuO+H_2SO_4->CuSO_4+H_2O\)
tỉ lệ 1 : 1 : 1 : 1
n(mol) a----------->a---------->a------------>a
\(PTHH:Fe_2O_3+3H_2SO_4->Fe_2\left(SO_4\right)_3+3H_2O\)
tỉ lệ 1 ; 3 : 1 : 3
n(mol) b--------->3b------------>b-------------->3b
Ta có hệ phương trình sau
\(\left\{{}\begin{matrix}80a+160b=24\\a+3b=0,4\end{matrix}\right.\\ < =>\left\{{}\begin{matrix}a=0,1\\b=0,1\end{matrix}\right.\\ =>\left\{{}\begin{matrix}n_{CuO}=0,1\left(mol\right)\\n_{Fe_2O_3}=0,1\left(mol\right)\end{matrix}\right.\\ =>\left\{{}\begin{matrix}m_{CuO}=n\cdot M=0,1\cdot80=8\left(g\right)\\m_{Fe_2O_3}=n\cdot M=0,1\cdot160=16\left(g\right)\end{matrix}\right.\)