|MadSci Network: Chemistry|
Yes (technically) and no (let's be realistic). TECHNICALLY SPEAKING... Let's assume there is about 100ml of sealable space in the sole of the shoe. (I think this is generous). The atomic weight of helium is 2g/mole or about 2g/22.4 liters of space. The air that would have been occupying that space is about 20% oxygen (32g/mole) and 80% nitrogen (28g/mole) giving a weighted average molecular weight for air of 28.8g/mole or 28.8g/22.4 liters of space. The difference in weight of the shoe would then be (28.8g - 2g)*(100/22400)= 0.12g One could expect the helium shoe to weigh 0.12g less than the otherwise identical air filled shoe. REALISTICALLY SPEAKING... The 0.12g difference is probably much less than the average variation in mass from one "identical" shoe to the next and it certainly is well within the variations in body weight and clothing weight one experiences on a day to day basis. Therefore the only observable weight difference between the helium shoes and other shoes will be in your wallet (a dollar bill weighs 1.0g... you can do the math!). Happy shopping! Jeremy.
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