a) \(n_{Al}=\dfrac{5,4}{27}=0,2\left(mol\right);n_{O_2}=\dfrac{13,44}{22,4}=0,6\left(mol\right)\)
PTHH: \(4Al+3O_2\xrightarrow[]{t^o}2Al_2O_3\)
Xét tỉ lệ: \(\dfrac{0,2}{4}< \dfrac{0,6}{3}\Rightarrow\) O2 dư
b) Theo PT: \(n_{Al_2O_3}=\dfrac{1}{2}n_{Al}=0,1\left(mol\right)\)
`=> m_{Al_2O_3} = 0,1.102 = 10,2 (g)`