What are electrons and how are they involved in creating and electric current?

 Electrons are particles orbiting a nucleus and depending on the material it can have one to many electrons more means better conductor. As a force EMF is impressed on this material electrons are forced to leave orbit and go where ? to the next nucleus but now here there are too many for balance so one leaves and so on. So as electrons flow one way the lack of one goes the other way. basically that is how electrons flow causing electric current as you put it.

The gas would begin to expand, and eventually the can would burst or explode.