[Diddly]

Hi,

Can anyone propose a mechanism as to why the solubility of sodium stannate decreases as temperature increases.

I use sodium stannate on my plant at work and this has me puzzled.

[ajkoer]

As a starting point it should be noted that this property of decreasing solubility is also seen in several sulfates.

In particular, the sulfate salts of Cadmium, Cerium, Lanthanum, Lithium, Manganese (II), Praseodymium and Ytterbium.

Three selenates also have this property, namely Cerium, Lanthanum and Lithium.  

Note the interesting overlap between selenates and sulfates.

I would investigate some of the more 'popular' metal salts for any explanations.