I've been trying to research lately on a way to rapidly produce gas to fill a balloon quickly through a chemical reaction that can be done w/ household materials. Is there any combination of reactants that can be picked up at a local hardware store or drug store to recreate this? Was not sure where to post this, so I ended up posting this in the General Off-Topic section. EDIT: I've also thought about baking soda + vinegar in a water bottle then putting a balloon on top. Just haven't tried it yet to see if it'll fill it quickly enough.