physicsfun on Instagram: "Reversible PEM Fuel Cell: this blue unit contains a Proton Exchange Membrane and platinum catalyst that enables an electrochemical reaction to generate electricity from combining hydrogen and oxygen into water (a hydrogen fuel cell), and if a current is supplied (say with two AA batteries) the process runs in reverse with the PEM assembly converting water in to hydrogen and oxygen (one side delivers O2 the other H2). This kit uses little “diving bell” structures to capt