Gọi số mol Zn, Al là a, b (mol)
=> 65a + 27b = 18,4 (1)
\(n_{O_2}=\dfrac{5,6}{22,4}=0,25\left(mol\right)\)
PTHH: 4Al + 3O2 --to--> 2Al2O3
b-->0,75b
2Zn + O2 --to--> 2ZnO
a-->0,5a
=> 0,5a + 0,75b = 0,25 (2)
(1)(2) => a = 0,2 (mol); b = 0,2 (mol)
=> \(\left\{{}\begin{matrix}\%m_{Zn}=\dfrac{0,2.65}{18,4}.100\%=70,65\%\\\%m_{Al}=\dfrac{0,2.27}{18,4}.100\%=29,35\%\end{matrix}\right.\)
\(2Zn+O_2\rightarrow 2ZnO \)
\(4Al+3O_2\rightarrow 2Al_2O_3 \)
\(n_{O_2}=\dfrac{5,6}{22,4}=0,25(mol) \)
\(Theo PT : x = 0,2 mol ; y = 0,2 mol \)
\(\%\)\(m_{Zn}=\dfrac{0,2.65}{18,4}.100\)\(\%\)\(=70,65 \)\(\%\)
\(\%\)\(m_{Al}=100\)\(\%\)\(-70,65=29,35\)\(\%\)
