Macro and Nano Experimental Facts Verifying the Colloidal Process in Silver Mirror Reaction

This lab activity explored the overlooked process of the silver mirror reaction by conducting experiments at both macro and nano scale. At the macro scale, laser irradiation on a reaction container revealed a gradually noticeable Tyndall effect. At the nano scale, silver nanoparticles (AgNPs) were collected at different periods during the reaction and characterized using UV–vis spectrometer and transmission electron microscopy (TEM). The UV–vis spectra exhibited a red-shift trend between characteristic wavelengths of AgNPs, and an increase in the absorption peak as time progressed. Additionally, TEM images and particle sizes revealed a gradual increase in the average diameter of AgNPs. These experimental facts verify the colloidal process in the silver mirror reaction. This lab activity was carried out by a group of students majoring in chemistry at Anhui Normal University. Satisfactory teaching effects have been achieved.