Originally Posted by JS
A hydrogen ballon will not explode. It burns quickly but quietly (other than the popping noise like any ballon, which depends on the partial pressure).
Look at the tape of the Hidenberg -- it didn't go "KABOOM!"; it burned like a house made of newpaper.
I dunno--we exploded a fair number of hydrogen-filled balloons in chemistry class when we had a "demo day" for the local 7th and 8th graders who came to visit the high school
NASA now believes the Hindenberg disaster wasn't even hydrogen related--the shell of the thing was an aluminum fabric, which apparently ignited and burned away. Hydrogen burns with a pale blue flame, whereas the bright orange flames seen then are much more characteristic of burning aluminum.