H2SO4+Ba(OH)2=BaSO4↓+2H2O
2H⁺+SO4⁻²+Ba⁺²+2OH⁻=BaSO4↓+2H2O
H2SO4+Mg=MgSO4+H2↑
2H⁺+SO4⁻²+Mg⁰=Mg⁺²+SO4⁻²+H2↑
2H⁺+Mg⁰=Mg⁺²+H2
FeO+H2SO4=FeSO4+H2O
FeO↓+2H⁺+SO4⁻²=Fe⁺²+SO4⁻²+H2O
FeO↓+2H⁺=Fe⁺²+H2O
Ba(NO3)2+H2SO4=BaSO4↓+2HNO3
Ba⁺²+2NO3⁻+2H⁺+SO4⁻²=BaSO4↓+2H⁺+2NO3⁻
Ba⁺²+SO4⁻²=BaSO4↓
2H2 + O2 = 2H2O V ( O2 ) = 0.022 л n( O2 ) =0.022 / 22.4 = 0.0009 моль n ( H2O ) = 0.0009 / 2 = 0.00045 моль m ( H2O ) = 0.00045 * 18 = 0.0081 г Ответ : 0.0081 г