As beautiophile noted, this can be done via titration and this will give you a very accurate answer.
How accurate do you need the test result to be? There are colorimetric methods that use a photometer and some reagents that will give you an accurate result. This type of test won't need chemical expertise to be able to do the test. You simply prepare the sample, add a reagent(s) and then read the result. You'll have to buy the photometer and reagents.
You can even buy simple test strips, put the test strip in the sample, wait the allotted time and then read the level of H202 in the sample by comparing it to a colour chart. Look up "Hydrogen Peroxide Test Strips as well as photometer test methods for hydrogen peroxide.
Test strips: https://selectscient...est-strips.html
Photometer: https://www.palintes...rogen-peroxide/
Edited by liberator, 01 March 2021 - 03:01 AM.