A.0.5g/LB.5g/LC.50g/LD.500g/L
A.H+B.S2-C.H2SD.OH-
A.把溶劑蒸發(fā)掉一半B.加入40g 溶質(zhì)質(zhì)量分?jǐn)?shù)為15%的CaCl2溶液C.把溶液蒸發(fā)掉20gD.加入2gCaCl2固體