Measurement Uncertainty on a Certificate
A primary benzoic acid standard is certified at 999.92 mg/g with an expanded uncertainty of 0.05 mg/g. What that interval promises, what the coverage factor does, and what the number never covers.
What Purity Actually Means: Impurities, Certificates and Specifications
A purity percentage is a statement about one chromatogram, one detector and one day, not about the contents of the bottle. This hub maps impurity thresholds, response factors, specifications and reference materials.
Identity and Purity: A Complete Guide to Analytical Methods for Small Molecules
Every analytical technique answers one question well and is blind to several others. This hub maps HPLC, GC-MS, NMR, MS, FTIR, XRPD and Karl Fischer titration onto the questions they can actually settle – and explains why regulators expect orthogonal evidence.