I am reading the ICP ASTM D4951 method, i have questions:
1. For preparing Internal Std with Cobalt, 10ppm to 20ppm is recommended, can explain the theory behind? I have VHG Co 6% and kerosine now.
2. How to prepare calibration standards and samples 1-5 mass% oil in solvent? I have V23 900ppm standard and 75cst white oil.Can give example if the total weight is 10g.