4 ms·

Combine with candles on a cake

• WalterBright 3y ago
  Hydrogen is a good lifting gas. The balloon only needs enough H to lift it. The rest of the balloon could be filled with nitrogen or CO2. The H concentration may be low enough to not burn.
  • isoprophlex 3y ago
    That is, I'm sorry to be so blunt, not a well thought out idea. The flammability range for hydrogen in air is 4% - 74%, and even though it ignites with difficulty at dilutions higher than 10%, you would still have to dilute it like mad in order to get a provably non-flammable lifting gas. 10% H2 in N2 is not good for lifting... let alone 4%. --- Oh, and, tri-atomic CO2 is very heavy (44 g/mol). So, waving the ideal gas law around, it really doesn't make sense to use that for lifting purposes at all when you have other, smaller things around.
    • WalterBright 3y ago
      My chemistry dates back to freshman chemistry long ago. So I am not a chemist. > The flammability range for hydrogen in air is 4% - 74%, and even though it ignites with difficulty at dilutions higher than 10%, you would still have to dilute it like mad in order to get a provably non-flammable lifting gas But it could not combust inside the balloon because H doesn't combine with N (at least I don't think it does!). It would have to be released, and then mixed with air to burn. If the balloon popped would it disperse faster than it could burn? I don't know, and simple chemistry would not provide an answer. One would have to do experiments.
      • WalterBright 3y ago
        Some other things to consider: 1. Pure nitrogen is lighter than air. Not enough to lift a balloon, but enough to make the balloon lighter than an air filled one. So it would be a good gas to mix with the hydrogen. Nitrogen gas is cheap, too. 2. Helium could be mixed in with the hydrogen, so the hydrogen would not be concentrated enough to ignite. This would reduce the quantity of helium needed.