Peachtree Playthings - Wack-A-Packs are memorable surprise greetings! To inflate, smack the pack and lightly shake, then throw on the floor! There will be a small "bang" as the balloon inflates and
EPBOT: And Now, John And I Explode Some Valentine Balloons
Expanding on Self-Inflating Balloons: Activities Involving Moles, Gas Laws, and Thermochemistry | Chemical Education Xchange