Theo gt ta có: $n_{Fe}=0,4(mol);n_{H_2SO_4}=0,25(mol)$
$Fe+H_2SO_4\rightarrow FeSO_4+H_2$
b, Ta có: $n_{H_2}=n_{H_2SO_4}=0,25(mol)\Rightarrow V_{H_2}=5,6(l)$
c, Sau phản ứng còn dư $n_{Fe}=0,4-0,25=0,15(mol)\Rightarrow m_{Fe}=8,4(g)$
(Các trường hợp nào bạn nhỉ?)
\(n_{Fe}=\dfrac{22.4}{56}=0.4\left(mol\right)\)
\(n_{H_2SO_4}=\dfrac{24.5}{98}=0.25\left(mol\right)\)
\(Fe+H_2SO_4\rightarrow FeSO_4+H_2\)
\(1............1\)
\(0.4.........0.25\)
\(LTL:\dfrac{0.4}{1}>\dfrac{0.25}{1}\Rightarrow Fedư\)
\(V_{H_2}=0.25\cdot22.4=5.6\left(l\right)\)
\(m_{Fe\left(dư\right)}=\left(0.4-0.25\right)\cdot56=8.4\left(g\right)\)