卫生球在家庭中常被放入衣柜或书橱中,用来防治毛料衣物和书籍被虫蛀。其主要成分是萘,是从煤中提取的一种有机物,非常容易发生升华现象。衣柜或书橱中的卫生球要不了多长时间就消失了,就是萘由固态直接变成了气态的结果。利用卫生球可以做一些非常有趣的化学小实验。 Health ball in the family often put in a closet or bookcase, used to control wool clothing and books are moth-eaten. Its main ingredient is naphthalene, an organic substance extracted from coal, which is very prone to sublimation. It takes less than a few minutes for the sanitary ball in the closet or bookcase to disappear, the result of the naphthalene turning from solid to gaseous. The use of health ball can do some very interesting experiments in chemistry.