Question

Cho 2,7g Al tác dụng \(O_2\). tÍNH \(V_{O_2}=?\left(đktc\right)\); \(m_{Al_2O_3}=?\)

Answer 1

\(n_{Al}=\dfrac{2.7}{27}=0.1\left(mol\right)\)

\(4Al+3O_2\underrightarrow{t^0}2Al_2O_3\)

\(0.1....0.075.....0.05\)

\(V_{O_2}=0.075\cdot22.4=1.68\left(l\right)\)

\(m_{Al_2O_3}=0.05\cdot102=5.1\left(g\right)\)

Answer 2

ta có: \(n_{Al}=0.1\left(mol\right)\)

PTHH

\(4Al+3O_2\underrightarrow{t^o}2Al_2O_3\)

4         3

0.1      x

\(=>x=0.075=n_{O_2}\)

\(=>V_{O_2}=0.075\cdot22.4=1.68\left(l\right)\)