Excuse me, is it illegal to put balloons in places where fireworks and firecrackers are prohibited? Is to blow up the balloon and then make a device to make the balloon burst automatically.

As long as fireworks are not set off, there is no illegal phenomenon. But hydrogen balloons are dangerous and will explode.

If we ignite pure hydrogen escaping from the conduit, it will burn quietly in oxygen, producing a light blue flame. The beaker wall is hot, indicating that a lot of heat is released during combustion. There are water drops on the inner wall of the beaker, which are water generated by the reaction of hydrogen and oxygen.

Take a paper tube with an open end, and introduce hydrogen from the lower end for a period of time to make the tube full of mixed gas of hydrogen and oxygen. He heard a loud noise after a quick ignition at the small hole. Air billow held the paper tube high and exploded. Combustible gas, flammable liquid vapor and flammable dust may explode when they are ignited. If the concentration of these combustible substances in the air is lower than or higher than the explosion limit, they can burn quietly without explosion when they are ignited.