Hướng dẫn:

${{n}_{{{H}_{2}}Olt}}={{V}_{{{H}_{2}}O}}.{{C}_{{{M}_{{{H}_{2}}O}}}}=1000.0,5=500\left( mol \right)$

  $2{{H}_{2}}O$  $\xrightarrow{dienphan}$ $2{{H}_{2}}+{{O}_{2}}$ 

  500         $\to $        500                                        (mol)

Theo phương trình ta có:

${{n}_{{{H}_{2}}Olt}}={{n}_{{{H}_{2}}lt}}=500\left( mol \right)$

$\Rightarrow {{n}_{{{H}_{2}}pu}}=80%.{{n}_{{{H}_{2}}lt}}=80%.500=400\left( mol \right)$

$\Rightarrow {{V}_{{{H}_{2}}}}=22,4.{{n}_{{{H}_{2}}pu}}=22,4.400=8960\left( l \right)$ 

$\Rightarrow $ Chọn đáp án D