Quote Originally Posted by Kirk Keyes View Post
First - I said I would try to use a better grade than technical and that I recommend others do as well.

Second - It all depends on your required limit for insoluble particles. If they are sufficiently small enough and there are very few of them, then who cares? You can easily filter a solution through a 0.45 um glass fiber filter and what gets through would be of no consequence, as they would remain suspended in the solution.

Third - I'm still working on that one.

Fourth - OK - it's still extra work to make the gallon.

Fifth - Your're saying that if I weigh a gram of liguid it is more precise than weighing a gram of solid? Please explain. The precision of my balance or scale is still the same. And if I go your method, then I have to trust that I have truely made a saturated solution. If I weigh the dry chemical, then I KNOW that I have exactly what I wieghed. At least to the accuracy of my balance or scale.

You're having a lot of fun, but really, your system is a lot of work and based on assumptions and requires extra skill (to know that you have actually saturated the solution).
Let me point out that the highest grades I have seen specified by Rio Tinto and others guarantee the sodium tetraborate decahydrate equivalent to be between 99.9 and 105 or even 110 %. That is due to uncertainty in the state of hydration. You do not know how accurately you are measuring when you measure by weight of dry powder or granules if you are looking for an accurate measurement of sodium tetraborate unless you know the exact state of hydration of all of your batch.

I don't see your argument that I do not know if I have a saturated solution. If I decant a clear liquid and cool it, I will soon know if it was saturated. If it sits long enough with excess borax at the bottom, and I stir ir periodically, I don't see how it cannot be saturated. If I weigh an accurate 4% solution to the nearest 0.1 gram I am certainly more accurate than measuring a solid whose concentration, so to speak, is not known any better than +/- 5%. The best way I can see to make sure of the state of hydration is to make a saturated solution. It must be commonly used as a method, for the weight percentage of borax decahydrate in a saturated solution is specfied vs. temperature to the hundredth of a percent in the Borax Decahydrate Product Profile by U. S. Borax.