a) PTHH: \(4Al+3O_2\underrightarrow{t^o}2Al_2O_3\)
Ta có: \(n_{Al}=\frac{2,7}{27}=0,1\left(mol\right)\)
\(\Rightarrow n_{Al_2O_3}=0,05mol\) \(\Rightarrow m_{Al_2O_3}=0,05\cdot102=5,1\left(g\right)\)
b) PTHH: \(Al+NaOH+H_2O\rightarrow NaAlO_2+\frac{3}{2}H_2\)
Theo PTHH: \(\left\{{}\begin{matrix}n_{NaOH}=n_{Al}=0,1mol\\n_{H_2}=\frac{3}{2}n_{Al}=0,15mol\end{matrix}\right.\) \(\Rightarrow\left\{{}\begin{matrix}C_{M_{NaOH}}=\frac{0,1}{0,5}=0,2\left(M\right)\\V_{H_2}=0,15\cdot22,4=3,36\left(l\right)\end{matrix}\right.\)
