@nicholejames wrote:
I wanted to confirm that the ACS test for Residue After Ignition does not have the analyst repeat the moistening with sulfuric acid and ignition until constant weight is achieved like Sulfated Ash- EP (2.4.14) or Residue on Ignition- USP (281).
You're correct that the ACS test for Residue After Ignition does not require the analyst to repeat the moistening with sulfuric acid and ignition until a constant weight is achieved, unlike the procedures for Sulfated Ash (EP 2.4.14) or Residue on Ignition (USP 281), which do require repeated cycles until a constant weight is obtained.
