Catalytic converters on automobiles use the metals rhodium and platinum as catalysts to convert harmful gases to carbon dioxide, nitrogen, and water. Which answer best explains why rhodium and platinum do not have to be continuously replaced in the system? (1 point)
1.) The useable life of the metals is longer than the life of the automobile.
2.) The metals speed up the reactions but are not used up in the reaction.
3.) The metals are too expensive to be replacing constantly.
4.) The metals are inhibitors in the reaction process and are in chemical equilibrium.