How long do foil balloons stay inflated with normal air?
If you're wondering how long do foil balloons stay inflated with normal air, the short answer is: a surprisingly long time, often weeks or even months if you treat them right. Unlike helium, which seems to have a mind of its own and escapes at the first chance it gets, plain old air is much more "loyal" to the balloon. It stays put because the molecules in the air we breathe are way bigger than those tiny, sneaky helium molecules that can slip through almost any material. ...