[erlenmeyerllc]

I have done numerous calculations and looked in all my old textbooks and have had problems figuring out how to prepare a sample of hydroperoxide solvated to a concentration of 85 mg/kg or 85 ppm if I am not mistaken. Any help would be much appreciated. With the numbers I've used thus far, it seems like I can't make a batch of approximately 3 liters or less without A LOT of solvent or a very, very accurate scale with about 10 decimal places. Any suggestions, advice?