TTex600:
Add a second nozzle pointing in the opposite direction from the one you started with, on the other side of the reaction chamber.
The Third law is honored, and movement (velocity) is nil.
Sorry, I had missed your point. You are of course correct.
But I was addressing the common misconception of the escaping exhaust of a jet or rocket "reacting" against the atmosphere behind the vehicle. I used to have to shoot down that "logic" in the classes I taught.
You are exactly right, the gases in the rocket chamber force against the forward wall, and that is where the reaction is felt.
