Possible problem with homemade alcohol?!
(please only answer if you have something related to the question and not your own philosophical opinion)
Answers:
1) You can live on JUST sugar for a good while because you're a complex organism and will take some time to succumb to lack of other nutritional needs. Yeast also eat sugar but JUST sugar won't sustain single-cell critters long-enough for a meaningful alcohol yield unless you use a particular strain of yeast that even brewers have given-up on isolating. In short, the yeast needs vitamins and minerals. In beer, they feast on complex starches and proteins from grain as well as on the converted sugar.
You're in luck. Brewing supply vendors sell "yeast nutrient." Add as directed to your sugar-water and you will get a good yield. Use "champagne yeast" and it will top-out to about 40-proof
2) The balloon has holes. It won't inflate. While you're at the brew-store (or website) get a stopper and airlock. They're cheap as hell, allow venting and keep-out contaminants. That's what they're for.
3) If you use a "water-trap" airlock the venting gas will make it bubble. Whether it takes 2 days or 2 months, if it's still "burping" it's still making alcohol.
4) Siphon-off the liquid avoiding the sediment on the bottom. Yeah, I know you're just fermenting sugar-water but the yeast are going to raise many generations of families who will grow-old, die and sink to the bottom. You WILL have a yeasty sediment. It won't hurt you but - come on - it's yeasty sediment.
Wanna' make it carbonated?
5) In a separate container you can add about 30ml of table sugar per gallon of liquid that you siphoned from your brew-tank. (best to dissolve it into as little water as possible first, add THAT to this bucket or whatever then siphon into it.) This gives the yeast just enough to ferment A LITTLE more.
6) Transfer to bottles than you know can hold pressure - used (but very clean) plastic soda or beer bottles are good. Screw-down the caps nice and tight.
7) When the bottles are hard, your pretty-much have Zima. (with a film of yeasty sediment to avoid when you pour. Pour smoothly and plan to leave the bottom 1/4 inch in the bottle.)
By the way, now you almost know how to make beer.
Also, it's a good idea to sanitize EVERY-DAMNED-THING that is going to touch your product. Your brew-supply place has great stuff for that, too if you're not a fan of bleach flavor.
Wong yeast.
Jay if you were old enough to drink you wouldn't be trying to make it...bad idea!