Praseodymium chloride - PrCl3·nH2O
This is a sample of praseodymium chloride, prepared by dissolving very pure praseodymium metal in reagent grade hydrochloric acid. The material has an unknown water content, probably much less than the pure crystalline compound PrCl3·7H2O. This compound is denoted as PrCl3·nH2O, with n probably quite close to 0. The material dissolves in water very easily, but its solutions are milky. Adding a tiny drop of hydrochloric acid to such a solution makes it totally clear.
The amount shown here is approximately 3.5 grams.
After one year of storage, the chemical has changed color. The solid has turned yellow with a beige tinge and lost its green color.