spot test
noun1
Chemistry, Natural sciences, Physical sciences The addition of a single drop of a reagent to a small sample as a qualitative analytical test for the presence of a specific compound or class of compounds.
- The DPA test referred to by Martz is a color spot test for a range of oxidizing compounds, which include but are not limited to nitrates.1998, Michael R Bromwich, The FBI Laboratory: An Investigation into Laboratory Practices & Alleged Misconduct: