Subject: why cant i get oxegen off of a steel eletrode?

This is an eletrolisis experiment.
  I have a cemistry book and it says that if the salt is consentrated (I 
interperted that as "super sacherated") the salt will be electrolized 
rather then the water, the products at the electodes: clorine and hydorgen 
(if the salt is "consentrated"). I am trying to produce oxegen and 
hydrogen.
 so I filled one container with 1 cup of water.  then put 1 1/2 teaspoons 
of salt in the container. on the left I put the steel anode and on the 
right I put the cathode.  then I connected an 18 volt dc trasformer to it. 
 after a wile the anode had rust deposits in it and the cathode was 
bubbleing with hyrdogen.  when I replaced the anode with pencil lead it 
bubbled too.
   Why can the carbon eletrode bubble oxegen while the steel electrode 
rusts? I know that iron and oxegen combine to make rust but I would think 
that at least some of the oxegen would bubble too. also the water got hot 
shortly. problaly cause the H3O+ ions where combineing with the OH- ions to 
produce water. the heat might have something to do with the production of 
rust.
sorry for spelling errors!
thanks, kyle

Re: why cant i get oxegen off of a steel eletrode?