n(H2) = \(\dfrac{20}{22,4}=\dfrac{25}{28}\left(mol\right)\)
n(O2) = \(\dfrac{20}{22,4}=\dfrac{25}{28}\)(mol)
2H2 + O2 --> 2H2O
Ban đầu \(\dfrac{25}{28}\): \(\dfrac{25}{28}\) (mol)
Phản ứng\(\dfrac{25}{56}\):\(\dfrac{25}{28}\): \(\dfrac{25}{56}\) (mol)
Sau pứ \(\dfrac{25}{56}\): 0 : \(\dfrac{25}{56}\) (mol)
Vậy H2 dư, O2 hết
V(H2 dư) = n.22,4 = \(\dfrac{25}{56}.22,4=10\left(l\right)\)