Mercury, which if present would interfere, is separated because of the insolubility of its sulphide in nitric acid.
The older one first recognised the insolubility of the problem.
It is separated from alumina by taking advantage of its insolubility in potassic hydrate.
From urates it is distinguished by its insolubility in warm water.
It is distinguished from corrosive sublimate by forming a black precipitate with caustic potash and by its insolubility in water.
It is frequently adulterated with jalap resin, a fraud readily detected by its insolubility in the last two menstrua.
The nearer it approaches to its original weight the better glue it is, thereby showing its degree of insolubility.
Rosalind was shirking a problem she dared not face from a cowardly conviction of its insolubility.
This is true as regards the incomprehensibility, but it is not the same with the insolubility.
As I have already mentioned the insolubility of glycocholic acid binds the color to the paper.
It was a tacit conviction of the learned during the Middle Ages that no such thing as an insoluble question existed. There might be matters that presented serious difficulties, but if you could lay them before the right man -- some Arab in Spain, for instance, omniscient by reason of studies into the details of which it was better not to inquire -- he would give you a conclusive answer. The real trouble was only to find your man. [Gertrude Bell, "The Desert and the Sown," 1907]
insoluble in·sol·u·ble (ĭn-sŏl'yə-bəl)