Câu 32:
PTHH: \(Al_2O_3+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2O\)
a_________3a (mol)
\(CuO+H_2SO_4\rightarrow CuSO_4+H_2O\)
b________b (mol)
Ta lập HPT: \(\left\{{}\begin{matrix}102a+80b=26,2\\3a+b=0,25\cdot2=0,5\end{matrix}\right.\) \(\Leftrightarrow\left\{{}\begin{matrix}a=0,1\\b=0,2\end{matrix}\right.\)
\(\Rightarrow\left\{{}\begin{matrix}\%m_{Al_2O_3}=\dfrac{0,1\cdot102}{26,2}\cdot100\%\approx38,93\%\\\%m_{CuO}=61,07\%\end{matrix}\right.\)
\(\Rightarrow\) Chọn D
