Gold isn’t inert, it just has bodyguards protecting it

Gold is weird. It’s one of the few metals that doesn’t really oxidize. Even silver and copper—from the same column of the periodic table—form weak oxides. Naively, you might expect that gold would tarnish just like silver. Gold also sits right next to platinum, but it has none of that metal’s catalytic properties. Then came gold nanoparticles that acted like catalysts, and we were confused by their apparent willingness to take part in chemical reactions. …