"It's amazing that something only an atom thick can be an impenetrable barrier. You can have gas on one side and vacuum or liquid on the other, and with a wall only one atom thick, nothing would go through it."
Vacuum
"It's amazing that something only an atom thick can be an impenetrable barrier. You can have gas on one side and vacuum or liquid on the other, and with a wall only one atom thick, nothing would go through it."