A.≥2.00g/100mL B.≥4.00g/100mL C.≥8.00g/100mL D.≥10.00g/100mL
A.0.0005g B.0.001g C.0.002g D.0.005g
A.取一定量試樣于坩堝中,將其中水分蒸干 B.炭化至無煙,于(600±25)℃灼燒2h C.重復(fù)加水濕潤,蒸干,高溫灼燒至無炭粒為止 D.置于高溫電爐中灼燒1h