Analytical chemistry

1879 Journal of the Chemical Society Abstracts  
Zeit. And. Chein., 1878, 4*59-461).-The advantage of the new indicator is that, unlike litmus, corallin, and phenolphthalein, it is not affected by the presence of large quantities of ammonium salts. It cannot, however, be used in presence of free ammonia. It is prepared by leaving some freshly-chopped orange peel in contact for 24 hours with absolute alcohol. The yellow extract is shaken with an equal bulk of ether to separate the essential oil, and the ethereal layer is removed. On adding
more » ... oved. On adding water, the alcoholic solution yields a colourless liquid in which acids produce no alteration, but which is changed to a beantiful lemon-yellow by alkalis. This indicator can be used only by daylight and for colourless liquids.
doi:10.1039/ca8793600396 fatcat:xxej6ntnbndylc6pgd7xfhncru