When environmental crews started cleaning up a closed government WWII laboratory, they discovered thousands of unlabeled gas cylinders (25 L) and wondered how to identify them. They knew that the cylinders mostly contained oxygen, methane, and helium, but some contained xenon or uranium hexafluoride. The cylinders are rusty and old, so they don't want to open each cylinder and send thousands of samples to an analytical laboratory. However, after scrounging around they find a scale, a pressure gauge, a large vat of water, several dozen packs of bubble gum, a large pile of snow in the parking lot, some firewood and matches, and their old thermodynamics textbook. Using your extensive knowledge of thermodynamics, suggest 2 or 3 (non-lethal) ways to the crew for identifying the correct gas in each cylinder using just these items. Or suggest how you might also use the Maxwell relationships with these items. Clearly state your assumptions, and provide as much detail on the procedures as possible.