Quote Originally Posted by Ole
Polysulfides tend to decompose to sulfur and sulfide, as in Na2S(n) -> Na2S + S(n-1).
(I'll use X_n for subscript and X^n for superscript like in TeX)

This is *very* interesting! So we have an equlibrium between S_n (eg. S_1 to S_8) and Na_2S_(n) in the solution, the white deposit probably being the stable (and rather inactive) S_8.

So if you lower the concentration of the polysulfide you will end up with less sulfur in the solution and S_8 is less likely to form. Does it sound reasonable that there is more reactive S_(n<8) in the solution at lower polysulfide-concentration and that this may be the reason for polysulifde-toners to speed up at higher dilutions?