How long do you bake your baking soda for?

[asylumdown]

I found the few times that I did it that it would practically solidify on the baking sheet, and the larger chunks didn't dissolve nearly as easily. Is that what you mean by clumping? It was like you would almost need to put it through a blender to get it back in to a fine powder that dissolved quickly. I was never sure if soda ash just has a lower solubility, or if it was the fact that I was trying to dissolve larger pieces (I'm sure I could have looked it up, but meh), but it was annoying enough that I stopped doing it and just stuck with regular old baking soda for my alk