Significant Digits

Significant Digits

By: Tim Loftus Measure it with a micrometer, mark it with a chalk line, then cut it with an axe. You probably experience some form of this every day. It’s common to mix analytical instrumentation, glassware, and reagents that have varying degrees of accuracy. Which...
Rounding Numbers

Rounding Numbers

By: Tim Loftus The analysis is complete, your technique was good, there were no interferences, and your equipment was operating at peak efficiency. How accurate is the result? That depends on how accurate your glassware and instrumentation is and on the purity of the...
Dilution Solutions

Dilution Solutions

By: Tim Loftus You have a 5.0 mg/L phosphate standard that exceeds the upper test limit for the low-range phosphate analytical procedure. For it to be considered adequate for a QA/QC known-concentration sample you’ll need to dilute it to a 0.2 mg/L concentration. Can...