Why does metal rust faster in saltwater?

Saltwater does not make a metal rust, but it accelerates the rusting process because electrons move more easily in saltwater than they do in pure water. read more

If you had pure iron, and put it into pure water, very little would happen, since there would be no oxygen to react with the iron. But if you put the pure iron into pure dry oxygen, very little would also happen. read more

Rust does not easily form in dry climate, but in a wet climate the oxygen can access the metal more easily through the water vapor, and rust occurs much faster. Pure water forms an acidic solution and allows the oxidation process to happen more easily, and salty water works even better since it is already a catalyst. read more