Well folks, you asked and we’re answering. That’s right we heard you. Peter Sterckx wants to know why do metal things grow. Well, here’s Sophia with an explanation. Corrosion is caused by a redox reaction, which is actually two simultaneous reactions in one: Reduction and Oxidation. (Oncscreen: 1) Reduction) A reduction reaction occurs when
some atoms or molecules gain electrons. I know, it’s confusing. (Onscreen: 2) Oxidation) Oxidation is where other atoms or molecules lose electrons. REDuction-OXidation, get it? (combine into “redox” text) A common example of corrosion is rusting, which happens to iron. You need just three ingredients for rust: an anode that easily gives up electrons. That’s iron. A cathode that easily accepts electrons. That’s oxygen. And lastly, you’ll need an electrolyte solution that shuttles ions between the cathode
and anode. (onscreen: water) Another example of redox is how Batteries also work using a redox reaction. But back to rust. Ever wonder why some metal objects rust after being left out in the rain? Well, water is the electrolyte
solution that helps rust form. Once these redox reactions occur,
iron (Fe) turns into hydrated ferric oxide (Fe2O3⋅nH2O) or rust. But why exactly does this happen? Well, iron and other metals that
corrode can’t really help it. The rusty form of some metals is
the thermodynamically favored state, meaning they would totally
prefer to be that way all the time, rather than stay in their pure elemental form. We humans just force it to be in a different state for our metallic needs. So rusting is the metal’s way of showing us who’s boss. If you have any more quick questions you’re dying for us to cover, drop them into the comments section.