a) \(n_{Al}=\frac{5,4}{54}=0,1\left(mol\right)\)
\(4Al+3O_2\underrightarrow{t^o}2Al_2O_3\)
0,1____0,075__0,05(mol)
\(V_{O_2}=0,075.22,4=1,68\left(l\right)\)
b) \(n_{O_2}=0,075\left(mol\right)\)
\(2KMnO_4\underrightarrow{t^o}K_2MnO_4+MnO_2+O_2\)
0,15________0,075_______________0,075(mol)
\(m_{KMnO4}=0,15.158=23,7\left(g\right)\)
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