Hai khí không màu không hóa nâu là \(\left\{{}\begin{matrix}N_2:x\left(mol\right)\\N_2O:y\left(mol\right)\end{matrix}\right.\)
\(\Rightarrow\left\{{}\begin{matrix}x+y=\dfrac{6,72}{22,4}=0,3\\28x+44y=18\cdot2\cdot0,3\end{matrix}\right.\)\(\Rightarrow\left\{{}\begin{matrix}x=0,15mol\\y=0,15mol\end{matrix}\right.\)
\(\Rightarrow n_{HNO_3}=12n_{N_2}+10n_{N_2O}=12\cdot0,15+10\cdot0,15=3,3\left(mol\right)\)
\(46Al+168HNO_3\rightarrow46Al\left(NO_3\right)_3+6N_2O+9N_2+84H_2O\)
0,9 3,3
\(m_{Al}=0,9\cdot27=24,3\left(g\right)\)