impure 托福专八

Impure drinking water is a cause of disease.

不洁的饮用水是引发疾病的一个原因。

An impure oxide of cobalt, used to produce a blue color in enamel and in the making of smalt.

浅的绿蓝色颜料，主要由钴和锡的氧化物组成。

The technological condition of Potassium Sulfate production from impure glaserite and impure Potassium chloride, is discussed in the paper,It is proved by experiment.

文章介绍了利用电解理论计算不纯净钾芒硝与不纯净氯化钾转化制取硫酸钾的工艺条件，并通过试验加以验证。