Gas molecules under pressure |
Adkins apparently thought this would be a simple geometry problem with a little bit of physics thrown in to make it more complex. That's more or less what he said in his introduction:
"Air, as well as gases such as hydrogen and helium, has mass. If you could put a gas on a scale, you’d find it has a specific weight that depends on the density of the particular kind of gas. However, you can figure the weight of gas in a cylinder if you calculate the volume of the cylinder and know the density of the gas it contains."
Our staffer who found that statement immediately blurted, "Wait: you need to know more!" but a quick scan of William's text showed that he didn't know that. Here's what W. D. told the OQ to do:
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The real answer? You need to calculate the number of moles of gas in a pressurized cylinder using the Ideal Gas Law, PV = nRT. You know pressure (P)... W. D. showed you how to calculate volume in liters (V), the universal gas constant (R) and the temperature (T) -- then solve the equation for n, the number of moles of gas. Then figure the mass at approximately 28 grams per mole of gas. In other words, a cylinder at 1000 psi contains a greater mass of gas than a cylinder at 14.7 psi.
Adkins obviously didn't know jack about this. The content editor obviously didn't know enough to correct him. And so, we have yet another case where we truly wish the Antisocial Network could hand out two Dumbass of the Day awards, but we can't – so W. D. gets another one all to himself (number three, for those who are counting).
¹ The original has been sent to the cleanup team by Leaf Group, but can still be accessed using the Wayback machine at archive.org. Its URL was ehow.com/how_5976192_figure-weight-gas-cylinder.html
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SI - CHEMISTRY
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