A:Fe3O4 溶于足量稀HNO3:Fe3O4+8H+=Fe2++2Fe3++4H2O
B:硫化钠的水解反应:S2-+H3O+ ⇌ HS-+H2O
C:将0.2mol/L的NH4Al(SO4)2溶液与0.3mol/L的Ba(OH)2溶液等体积混合:2Al3++3SO42-+3Ba2++6OH-=2Al(OH)3↓+3BaSO4↓
D:NH4HCO3溶液与足量Ba(OH)2溶液混合:HCO3-+Ba2++OH-=BaCO3↓+H2O
为了清晰地观察到物质的溶解过程,我们用一种____的物质代替食盐做溶解实验。
My mother often _____ me ____ housework on Sunday.