When trying to remove rust from a chrome surface, establish that it is indeed chrome and not just any other metal. If it is, clean the surface wit regular soap and water to expose the rust surface then dab it with polish. Using a steel wool and circular motions, rub the rusty area al the while adding polish to the surface or the steel wool. Rinse periodically to expose the remaining rust. Once done, rinse and finally polish the surface to a shine. Soaking rusted chrome substances in a tub of oxalic acid and water then polishing will also help.