Unfortunately, no one has followed a balloon up to see what really happens up there as far as I know. And on top of that, you have to keep adding air without tying a knot to over-inflate a balloon ...

Production of carbon dioxide from reaction of citric acid and baking soda ...

Seven colourful balloons inflated at Innes Common by Hamilton Lake ... Ben first experienced Balloons Over Waikato when he was 3 months old. “We go every year,” Ken said.