/community-hubs/deltav-community-connect/b/delta-vweblog/posts/checklist-for-best-ph-measurement-performanceThe composition measurement with by far the greatest sensitivity and rangeability is pH.   Consider that pH routinely detects changes at 7 pH to the 9th decimal place and for a 0-14 pH scale covers 14 orders of magnitude of hydrogen ion concentrationen-USTelligent Community 13