Subject: Test for palladium
Are there any tests to identify palladium metal?
There are some tests which can be used, for example:
-Relative to platinum, palladium will form a bluish oxide film when heated in a Bunsen flame and then, unlike base metals, will if heated in a reducing flame revert back to a silver colour. Conversely if, once the oxide film is formed, the temperature is increased to ~1000ºC the oxide again reverts back to pure metal.
-Palladium will be slowly dissolved by concentrated nitric acid to colour the solution orange/brown. Platinum will not be affected and nickel alloys will produce a solution with a green colouration.
Other physical and chemical properties can be found through The PGM Database.
Answer posted 14 February 2007
Submitted by: Ms Sara Coles
Affiliation: Johnson Matthey Technology Review
Answered by: Robert McGrath
Affiliation: Johnson Matthey Noble Metals