<div>We present here an experimental session for undergraduate students,
based on the reaction monitoring of the degradation of an organic
pollutant (para-nitrophenol) by a Fenton-like reaction, catalysed by
magnetite particles. <br></div><div>During the session, students
realized a follow-up of the reaction by Gas Chromatography with an
internal standard, and by UV-Visible spectrophotometry. <br></div>This session was a good starting point to numerous discussions about analytical chemistry, environmental chemistry.