impure 托福专八

Impure drinking water is a cause of disease.

洁饮用水是引发疾病一个原因。

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

浅绿蓝色颜料，主要由钴和锡氧物组成。

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质溶液理论计算净钾芒硝与净氯钾转硫酸钾工艺条件，并通过试验加以验证。