I'm trying to understand why my solution of Iron (II) sulfate dissolved in water turns brown.
What I'm attempting is recrystallization of Iron (II) sulfate moss killer to purify it, but I have to deal with a lot of brown sludge forming on the bottom.
There are nice green crystals forming but it always has this brown on them.
Is this caused by oxidation and is it Iron oxide that is formed?
Is it because I heat the solution too much? It seems to get worse with heat.
Is there any way to prevent this?
I'm very new to this so any help would be greatly appreciated.
