The short answer would be none - alka-setlzer fizzes releasing carbon dioxide but that would insufficient due to the lack of pressure.
Why would we be that sad to find that out?!
Hot air balloons generally fly better with a little breeze, they don't fly well in hot weather.
You're going to have to do better than that. By the time you are in 6th grade science, you should already know mixing baking soda and vinegar will produce carbon dioxide gas, but it won't produce enough gas pressure to pop the balloon. I have been a science fair judge, and the first question I asked myself when I read the papers the students wrote was, "did this student learn anything new?" If I were to judge your project the way you wrote it, I would think to myself, "this student did an experiment he already knew the results of, so he did not learn anything new." It won't pop the balloon unless you got hold of a really bad batch of balloons, but it will blow it up and you can do quite a few fun experiments, where you WILL learn something new, with baking soda, vinegar and balloons. Start with buying a big box of baking soda, a gallon of vinegar and a bag of balloons that are the same. Next, make a measuring gauge--if you got 12-inch balloons, cut a hole 30cm in diameter in a piece of cardboard. Then inflate balloons in different ways, and time how long it takes them to be 30cm in diameter. You could... * vary the amount of baking soda * dilute the vinegar * use vinegar at different temperatures * use different amounts of vinegar * inflate a balloon that's been in the freezer all night, one that's been at room temperature and one you warmed up in a sink of hot water, to see if the different temperature makes the rubber more or less pliable * use different acids, like maybe vinegar, orange juice and lemon juice * stretch one balloon before blowing it up to see if that really does anything
White wine vinegar is the better substitute for rice vinegar.
Vinegar
Salt &vinegar
yes
Vinegar reacts with metals, that we never see vinegar in metal containers.
Because they taste better if they have vinegar.
Hydrogen is lighter than helium. So hydrogen balloon will float better than helium.
Vinegar. Pledge is a wax; it will gunk up a window or mirror.
it absorbs vinegar more quickly and much more efficiently.