Đáp án:

QED...

Giải thích các bước giải:

`n_Y=2x(mol);n_Z=3x(mol)`

`X^0->X^{+3}+3e`

`Y^0->Y^{+2}+2e`

`Z^0->Z^{+1}+1e`

Bảo toàn electron:

`3n_X+2n_Y+n_Z=n_{NO_2}+3n_{NO}`

`->n_{NO_2}+3n_{NO}=3x+2.2x+3x=10x(mol)`

`2H^{+}+NO_3^{-}+1e->NO_2+H_2O`

`4H^{+}+NO_3^{-}+3e->NO+2H_2O`

Bảo toàn electron:

`n_{HNO_3}=2n_{NO_2}+4n_{NO}=(n_{NO_2}+3n_{NO})+(n_{NO_2}+n_{NO})`

`=10x+V/{22,4}(mol)`

`->m_{HNO_3}=63(10x+V/{22,4})(g)`

`->m_{HNO_3\ du}=25\%.63.(10x+V/{22,4})=15,75(10x+V/{22,4})(g)`

`->m_{HNO_3\ bd}=15,75(10x+V/{22,4})+63(10x+V/{22,4})(g)`

`->y=78,75(10x+V/{22,4})=1,25(10x+V/{22,4}).63(g)`