wackyvorlon - 6-7-2008 at 18:16
I'm still just starting to work with chemistry, and am very much a beginner. So this may be a silly question. I also don't have hard numbers for the
amounts involved, for which I apologize. I'm still getting my equipment together, and at this point it is severely lacking. I did this using an
experiment from the Thames and Kosmos C1000 kit.
I prepared a solution of potassium hexacyanoferrate, and a solution of ammonium iron sulfate. I poured 50ml of distilled water into a measuring cup,
and added ten drops of each solution. This resulted in a very pale blue colouration. I proceeded to add another ten drops of each, and it became
much darker. I noticed that when I added more ammonium iron sulfate that colour would become darker, but adding potassium hexacyanoferrate did not.
I determined this by adding ten drops of the ammonium iron sulfate solution, noted the change. Ten drops of potassium hexacyanoferrate of solution
did not result in a colour change. Then I added ten drops of ammonium iron sulfate solution, noted a colour change. An additional ten drops of
ammonium iron sulfate solution resulted in further colour change.
This could be a case of my simply not doing enough experimentation, but it appears that the colour change is more strongly influenced by the ammonium
iron sulfate solution. Any thoughts are greatly appreciated.
pantone159 - 6-7-2008 at 19:06
It depends on the concentration of your solutions!
There is one ferric ion to go with each ferrocyanide (or ferrous and ferricyanide, I couldn't tell which you meant). The particle size of the
precipitate, and hence the physical qualities of the prussian blue, depend on a lot of things.