Briefly, whole samples (about 10 mL) were measured into a quartz beaker, then 10 mL of HNO3 was added, and the mixturewas gently heated on a hot plate until the brown fumes given off by the reaction turned white
Briefly, whole samples (about 10 mL) were measured into a quartz beaker, then 10 mL of HNO3 was added, and the mixturewas gently heated on a hot plate until the brown fumes given off by thereaction turned white